Android应用Loaders全面详解及源码浅析
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1 背景
在Android中任何耗时的操作都不能放在UI主线程中，所以耗时的操作都需要使用异步实现。同样的，在ContentProvider中也可能存在耗时操作，这时也该使用异步操作，而3.0之后最推荐的异步操作就是Loader。它可以方便我们在Activity和Fragment中异步加载数据，而不是用线程或AsyncTask，他的优点如下：
- 提供异步加载数据机制；
- 对数据源变化进行监听，实时更新数据；
- 在Activity配置发生变化（如横竖屏切换）时不用重复加载数据；
- 适用于任何Activity和Fragment；
PS：由于在我们现在的多个项目中都大量的使用了Loader来处理数据加载（而且由于粗心跳过几个坑，譬如Loader ID重复导致数据逻辑异常、多线程中restartLoader导致Loader抛出异常（最后保证都在UI线程中执行即可）等），所以接下来我们进行下使用及源码浅析。
【工匠若水 http://blog.csdn.net/yanbober 转载请注明出处。点我开始Android技术交流】
PPPS：前方高能，文章巨长，请做好心理准备（您可以选择通过左上角目录点击索引到感兴趣的章节直接查看，或者，或者，或者直接高能往下看）。
2 基础使用实例
该基础实例讲解完全来自于官方文档，详细可以点击我查看英文原文。
既然接下来准备要说说他的使用强大之处了，那不妨我们先来一张图直观的感性认识下不用Loader（左）与用Loader（右）对我们开发者及代码复杂度和框架的影响吧，如下：
2-1 Loader API概述说明
如下是我们开发中常用的一些Loader相关接口：
2-2 在应用中使用Loader
在我们开发的一个App里，使用Loader时常规的步骤包含如下一些操作需求：
- 一个Activity或Fragment；
- 一个LoaderManager实例；
- 一个CursorLoader，从ContentProvider加载数据；
- 一个LoaderManager.LoaderCallbacks实现，创建新Loader及管理已存在Loader；
- 一个组织Loader数据的Adapter，如SimpleCursorAdapter；
下面我们看下具体流程。
2-2-1 启动一个Loader（initLoader）
一个Activity或Fragment中LoaderManager管理一个或多个Loader实例，每个Activity或Fragment只有一个LoaderManager，我们可以在Activity的onCreate()或Fragment的onActivityCreated()里初始化一个Loader。例如：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Prepare the loader. Either re-connect with an existing one,</span><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// or start a new one.</span>getLoaderManager().initLoader(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>);</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li></ul>
可以看见上面的initLoader()方法有三个参数：
- 第一个参数代表当前Loader的ID；
- 第二个参数代表提供给Loader构造函数的参数，可选；
- 第三个参数代表LoaderManager.LoaderCallbacks的回调实现；
上面initLoader()方法的调用确保了一个Loader被初始化和激活的状态，该方法的调运有如下两种结果：
- 如果代表该Loader的ID已经存在，则后面创建的Loader将直接复用已经存在的；
- 如果代表该Loader的ID不存在，initLoader()会触发LoaderManager.LoaderCallbacks回调的onCreateLoader()方法创建一个Loader；
可以看见通过initLoader()方法可以将LoaderManager.LoaderCallbacks实例与Loader进行关联，且当Loader的状态变化时就被回调。所以说，如果调用者正处于其开始状态并且被请求的Loader已经存在，且已产生了数据，那么系统会立即调用onLoadFinished()（在initLoader()调用期间），所以你必须考虑到这种情况的发生。
当然了，intiLoader()会返回一个创建的Loader，但是你不用获取它的引用，因为LoadeManager会自动管理该Loader的生命周期，你只用在它回调提供的生命周期方法中做自己数据逻辑的处理即可。
2-2-2 重启一个Loader（restartLoader）
通过上面initLoader()方法介绍我们可以知道initLoader调运后要么得到一个ID已存在的Loader，要么创建一个新的Loader；但是有时我们想丢弃旧数据然后重新开始创建一个新Loader，这可怎么办呢？别担心，要丢弃旧数据调用restartLoader()即可。例如，SearchView.OnQueryTextListener的实现重启了Loader，当用户查询发生变化时Loader需要重启，如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">onQueryTextChanged</span>(String newText) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Called when the action bar search text has changed. Update</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// the search filter, and restart the loader to do a new query</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// with this filter.</span> mCurFilter = !TextUtils.isEmpty(newText) ? newText : <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; getLoaderManager().restartLoader(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>;}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li></ul>上面方法的参数啥的和再上面的init方法类似，就不再罗嗦了。
2-2-3 使用LoaderManager Callbacks
LoaderManager.LoaderCallbacks是LoaderManager的回调交互接口。LoaderManager.LoaderCallbacks包含如下三个方法：
- onCreateLoader()
实例化并返回一个新创建给定ID的Loader对象； - onLoadFinished()
当创建好的Loader完成了数据的load之后回调此方法； - onLoaderReset()
当创建好的Loader被reset时调用此方法，这样保证它的数据无效；
2-2-3-1 onCreateLoader说明
当你尝试使用一个Loader（譬如通过initLoader()方法），它会检查给定Loader的ID是否存在，如果不存在就触发LoaderManager.LoaderCallbacks里的onCreateLoader()方法创建一个新Loader。创建新Loader实例典型的做法就是通过CursorLoader类创建，不过你也可以自定义一个继承自Loader的子类来实现自己的Loader。
下面的例子中我们通过onCreateLoader()回调创建一个CursorLoader实例，使用CursorLoader的构造方法创建实例时需要一些参数去查询一个ContentProvider。具体参数如下：
- uri
准备获取内容的URI。 - projection
要返回的列key list，null表示返回所有列，但是返回所有列很多时候会降低性能； - selection
要返回的行过滤，也就是SQL中的WHERE语句，null代表返回uri指定的所有行； - selectionArgs
用来替换上面selection中包含的“？”； - sortOrder
结果的行排序，也就是SQL中的ORDER BY，传递null则无序；
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// If non-null, this is the current filter the user has provided.</span>String mCurFilter;...<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> Loader<Cursor> <span class="hljs-title" style="box-sizing: border-box;">onCreateLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, Bundle args) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// This is called when a new Loader needs to be created. This</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// sample only has one Loader, so we don't care about the ID.</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// First, pick the base URI to use depending on whether we are</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// currently filtering.</span> Uri baseUri; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCurFilter != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { baseUri = Uri.withAppendedPath(Contacts.CONTENT_FILTER_URI, Uri.encode(mCurFilter)); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { baseUri = Contacts.CONTENT_URI; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Now create and return a CursorLoader that will take care of</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// creating a Cursor for the data being displayed.</span> String select = <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"(("</span> + Contacts.DISPLAY_NAME + <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" NOTNULL) AND ("</span> + Contacts.HAS_PHONE_NUMBER + <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"=1) AND ("</span> + Contacts.DISPLAY_NAME + <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" != '' ))"</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> CursorLoader(getActivity(), baseUri, CONTACTS_SUMMARY_PROJECTION, select, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, Contacts.DISPLAY_NAME + <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" COLLATE LOCALIZED ASC"</span>);}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li></ul>2-2-3-2 onLoadFinished说明
当创建好的Loader完成数据加载时回调此方法，我们要确保该方法在Loader释放现有维持的数据之前被调用。在这里我们应该移除所有对旧数据的使用（因为旧数据不久就会被释放），但是不用释放旧数据，因为Loader会帮我们完成旧数据的释放。
Loader一旦知道App不再使用旧数据就会释放掉。例如，如果数据来自CursorLoader里的一个Cursor，我们不应该自己在代码中调用close()方法；如果一个Cursor正在被放置到一个CursorAdapter时我们应当使用swapCursor()进行新数据交换，这样正在被放置的旧的Cursor就不会被关掉，也就不会导致Adapter的加载异常。
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// This is the Adapter being used to display the list's data.</span>SimpleCursorAdapter mAdapter;...<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoadFinished</span>(Loader<Cursor> loader, Cursor data) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Swap the new cursor in. (The framework will take care of closing the</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// old cursor once we return.)</span> mAdapter.swapCursor(data);}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li></ul>2-2-3-3 onLoaderReset说明
当实例化好的Loader被重启时该方法被回调，这里会让Loader的数据置于无效状态。这个回调方法其实就是为了告诉我们啥时候数据要被释放掉，所以我们应该在这个时候移除对它的引用。如下移除实例：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// This is the Adapter being used to display the list's data.</span>SimpleCursorAdapter mAdapter;...<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoaderReset</span>(Loader<Cursor> loader) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// This is called when the last Cursor provided to onLoadFinished()</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// above is about to be closed. We need to make sure we are no</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// longer using it.</span> mAdapter.swapCursor(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>);}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li></ul>2-2-4 Loader使用实例实战
下面这个实例是一个Fragment，模拟的是用ListView显示通讯录的实时匹配查询结果，使用CursorLoader管理通讯录Provider查询。如下源码，比较简单，注释也很丰富了，所以不过多解释：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">CursorLoaderListFragment</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ListFragment</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">implements</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">OnQueryTextListener</span>, <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">LoaderManager</span>.<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">LoaderCallbacks</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">Cursor</span>> {</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// This is the Adapter being used to display the list's data.</span> SimpleCursorAdapter mAdapter; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// If non-null, this is the current filter the user has provided.</span> String mCurFilter; <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onActivityCreated</span>(Bundle savedInstanceState) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>.onActivityCreated(savedInstanceState); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Give some text to display if there is no data. In a real</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// application this would come from a resource.</span> setEmptyText(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"No phone numbers"</span>); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// We have a menu item to show in action bar.</span> setHasOptionsMenu(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Create an empty adapter we will use to display the loaded data.</span> mAdapter = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> SimpleCursorAdapter(getActivity(), android.R.layout.simple_list_item_2, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> String[] { Contacts.DISPLAY_NAME, Contacts.CONTACT_STATUS }, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span>[] { android.R.id.text1, android.R.id.text2 }, <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>); setListAdapter(mAdapter); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Prepare the loader. Either re-connect with an existing one,</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// or start a new one.</span> getLoaderManager().initLoader(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onCreateOptionsMenu</span>(Menu menu, MenuInflater inflater) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Place an action bar item for searching.</span> MenuItem item = menu.add(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Search"</span>); item.setIcon(android.R.drawable.ic_menu_search); item.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM); SearchView sv = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> SearchView(getActivity()); sv.setOnQueryTextListener(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); item.setActionView(sv); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">onQueryTextChange</span>(String newText) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Called when the action bar search text has changed. Update</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// the search filter, and restart the loader to do a new query</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// with this filter.</span> mCurFilter = !TextUtils.isEmpty(newText) ? newText : <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; getLoaderManager().restartLoader(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">onQueryTextSubmit</span>(String query) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Don't care about this.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onListItemClick</span>(ListView l, View v, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> position, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">long</span> id) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Insert desired behavior here.</span> Log.i(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"FragmentComplexList"</span>, <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Item clicked: "</span> + id); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// These are the Contacts rows that we will retrieve.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> String[] CONTACTS_SUMMARY_PROJECTION = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> String[] { Contacts._ID, Contacts.DISPLAY_NAME, Contacts.CONTACT_STATUS, Contacts.CONTACT_PRESENCE, Contacts.PHOTO_ID, Contacts.LOOKUP_KEY, }; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> Loader<Cursor> <span class="hljs-title" style="box-sizing: border-box;">onCreateLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, Bundle args) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// This is called when a new Loader needs to be created. This</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// sample only has one Loader, so we don't care about the ID.</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// First, pick the base URI to use depending on whether we are</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// currently filtering.</span> Uri baseUri; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCurFilter != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { baseUri = Uri.withAppendedPath(Contacts.CONTENT_FILTER_URI, Uri.encode(mCurFilter)); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { baseUri = Contacts.CONTENT_URI; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Now create and return a CursorLoader that will take care of</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// creating a Cursor for the data being displayed.</span> String select = <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"(("</span> + Contacts.DISPLAY_NAME + <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" NOTNULL) AND ("</span> + Contacts.HAS_PHONE_NUMBER + <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"=1) AND ("</span> + Contacts.DISPLAY_NAME + <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" != '' ))"</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> CursorLoader(getActivity(), baseUri, CONTACTS_SUMMARY_PROJECTION, select, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, Contacts.DISPLAY_NAME + <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" COLLATE LOCALIZED ASC"</span>); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoadFinished</span>(Loader<Cursor> loader, Cursor data) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Swap the new cursor in. (The framework will take care of closing the</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// old cursor once we return.)</span> mAdapter.swapCursor(data); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoaderReset</span>(Loader<Cursor> loader) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// This is called when the last Cursor provided to onLoadFinished()</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// above is about to be closed. We need to make sure we are no</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// longer using it.</span> mAdapter.swapCursor(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>); }}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li><li style="box-sizing: border-box; padding: 0px 5px;">37</li><li style="box-sizing: border-box; padding: 0px 5px;">38</li><li style="box-sizing: border-box; padding: 0px 5px;">39</li><li style="box-sizing: border-box; padding: 0px 5px;">40</li><li style="box-sizing: border-box; padding: 0px 5px;">41</li><li style="box-sizing: border-box; padding: 0px 5px;">42</li><li style="box-sizing: border-box; padding: 0px 5px;">43</li><li style="box-sizing: border-box; padding: 0px 5px;">44</li><li style="box-sizing: border-box; padding: 0px 5px;">45</li><li style="box-sizing: border-box; padding: 0px 5px;">46</li><li style="box-sizing: border-box; padding: 0px 5px;">47</li><li style="box-sizing: border-box; padding: 0px 5px;">48</li><li style="box-sizing: border-box; padding: 0px 5px;">49</li><li style="box-sizing: border-box; padding: 0px 5px;">50</li><li style="box-sizing: border-box; padding: 0px 5px;">51</li><li style="box-sizing: border-box; padding: 0px 5px;">52</li><li style="box-sizing: border-box; padding: 0px 5px;">53</li><li style="box-sizing: border-box; padding: 0px 5px;">54</li><li style="box-sizing: border-box; padding: 0px 5px;">55</li><li style="box-sizing: border-box; padding: 0px 5px;">56</li><li style="box-sizing: border-box; padding: 0px 5px;">57</li><li style="box-sizing: border-box; padding: 0px 5px;">58</li><li style="box-sizing: border-box; padding: 0px 5px;">59</li><li style="box-sizing: border-box; padding: 0px 5px;">60</li><li style="box-sizing: border-box; padding: 0px 5px;">61</li><li style="box-sizing: border-box; padding: 0px 5px;">62</li><li style="box-sizing: border-box; padding: 0px 5px;">63</li><li style="box-sizing: border-box; padding: 0px 5px;">64</li><li style="box-sizing: border-box; padding: 0px 5px;">65</li><li style="box-sizing: border-box; padding: 0px 5px;">66</li><li style="box-sizing: border-box; padding: 0px 5px;">67</li><li style="box-sizing: border-box; padding: 0px 5px;">68</li><li style="box-sizing: border-box; padding: 0px 5px;">69</li><li style="box-sizing: border-box; padding: 0px 5px;">70</li><li style="box-sizing: border-box; padding: 0px 5px;">71</li><li style="box-sizing: border-box; padding: 0px 5px;">72</li><li style="box-sizing: border-box; padding: 0px 5px;">73</li><li style="box-sizing: border-box; padding: 0px 5px;">74</li><li style="box-sizing: border-box; padding: 0px 5px;">75</li><li style="box-sizing: border-box; padding: 0px 5px;">76</li><li style="box-sizing: border-box; padding: 0px 5px;">77</li><li style="box-sizing: border-box; padding: 0px 5px;">78</li><li style="box-sizing: border-box; padding: 0px 5px;">79</li><li style="box-sizing: border-box; padding: 0px 5px;">80</li><li style="box-sizing: border-box; padding: 0px 5px;">81</li><li style="box-sizing: border-box; padding: 0px 5px;">82</li><li style="box-sizing: border-box; padding: 0px 5px;">83</li><li style="box-sizing: border-box; padding: 0px 5px;">84</li><li style="box-sizing: border-box; padding: 0px 5px;">85</li><li style="box-sizing: border-box; padding: 0px 5px;">86</li><li style="box-sizing: border-box; padding: 0px 5px;">87</li><li style="box-sizing: border-box; padding: 0px 5px;">88</li><li style="box-sizing: border-box; padding: 0px 5px;">89</li><li style="box-sizing: border-box; padding: 0px 5px;">90</li><li style="box-sizing: border-box; padding: 0px 5px;">91</li><li style="box-sizing: border-box; padding: 0px 5px;">92</li><li style="box-sizing: border-box; padding: 0px 5px;">93</li><li style="box-sizing: border-box; padding: 0px 5px;">94</li><li style="box-sizing: border-box; padding: 0px 5px;">95</li><li style="box-sizing: border-box; padding: 0px 5px;">96</li><li style="box-sizing: border-box; padding: 0px 5px;">97</li><li style="box-sizing: border-box; padding: 0px 5px;">98</li><li style="box-sizing: border-box; padding: 0px 5px;">99</li><li style="box-sizing: border-box; padding: 0px 5px;">100</li><li style="box-sizing: border-box; padding: 0px 5px;">101</li><li style="box-sizing: border-box; padding: 0px 5px;">102</li><li style="box-sizing: border-box; padding: 0px 5px;">103</li><li style="box-sizing: border-box; padding: 0px 5px;">104</li><li style="box-sizing: border-box; padding: 0px 5px;">105</li></ul>到此整个Loader基础使用就介绍完了，关于Loader的高级功能，譬如自定义Loader等内容这里先不贴代码说明，因为在这里一下子说完都会觉得蒙圈，而且接受难度也比较大，所以我们在上面这些基础铺垫之后乘热先来源码浅析，有了源码浅析把持住全局结构后再去用Loader的高级用法就会觉得得心应手许多。
【工匠若水 http://blog.csdn.net/yanbober 转载请注明出处。点我开始Android技术交流】
3 源码浅析
和上面的基本使用介绍一样，关于Loader的源码浅析过程会涉及到Activity、Fragment、LoaderManager、Loader、AsyncLoader、CursorLoader等类。所以我们分析的过程还是和以前一样，依据使用顺序进行分析。
我们在分析之前先来看一个Loader框架概要图,如下：
通过上面图和前面的基础实例你会发现Loader的框架和各个类的职责都很明确。Activity和Fragment管理LoaderManager，LoaderManager管理Loader，Loader得到数据后触发在LoaderManager中实现的Loader的callback接口，LoaderManager在接收到Loader的callback回传调运时触发我们Activity或Fragment中实现的LoaderManager回调callback接口，就这样就实现了Loader的所有功能，而我们平时写代码一般只用关心LoaderManager的callback实现即可；对于自定义Loader可能还需要关心AsyncTaskLoader子类的实现。
3-1 Activity及Fragment中LoadManager的管理浅析
首先我们都知道，在使用Loader的第一步就是在Activity或者Fragment中获取LoaderManager实例，所以我们先来看下Activity和Fragment是如何管理这些LoaderManager的。
先来看看Fragment中的LoaderManager，如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> class FragmentState implements Parcelable { ...... LoaderManagerImpl mLoaderManager; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mLoadersStarted; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mCheckedForLoaderManager; ...... <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//fragment中获取LoaderManager办法</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> LoaderManager <span class="hljs-title" style="box-sizing: border-box;">getLoaderManager</span>() { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//可以看见，一个Fragment只有一个LoaderManager</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoaderManager != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mLoaderManager; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mActivity == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> IllegalStateException(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Fragment "</span> + <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span> + <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" not attached to Activity"</span>); } mCheckedForLoaderManager = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//从Activity中获取LoaderManager，传入的mWho为当前Fragment的识别key，然后create传入true表示创建！！！！！！</span> mLoaderManager = mActivity.getLoaderManager(mWho, mLoadersStarted, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mLoaderManager; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onStart</span>() { mCalled = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!mLoadersStarted) { mLoadersStarted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!mCheckedForLoaderManager) { mCheckedForLoaderManager = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//如果还没调运过getLoaderManager，那就尝试获取LoaderManager，传入的create为false！！！！！</span> mLoaderManager = mActivity.getLoaderManager(mWho, mLoadersStarted, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//生命周期依附上LoaderManager</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoaderManager != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mLoaderManager.doStart(); } } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onDestroy</span>() { mCalled = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!mCheckedForLoaderManager) { mCheckedForLoaderManager = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//如果还没调运过getLoaderManager，那就尝试获取LoaderManager，传入的create为false！！！！！</span> mLoaderManager = mActivity.getLoaderManager(mWho, mLoadersStarted, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//生命周期依附上LoaderManager</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoaderManager != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mLoaderManager.doDestroy(); } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> performStart() { ...... mCalled = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; onStart(); ...... <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//生命周期依附上LoaderManager</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoaderManager != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mLoaderManager.doReportStart(); } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> performStop() { ...... mCalled = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; onStop(); ...... <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoadersStarted) { mLoadersStarted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!mCheckedForLoaderManager) { mCheckedForLoaderManager = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//如果还没调运过getLoaderManager，那就尝试获取LoaderManager，传入的create为false！！！！！</span> mLoaderManager = mActivity.getLoaderManager(mWho, mLoadersStarted, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoaderManager != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//生命周期依附上LoaderManager</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mActivity == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> || !mActivity.mChangingConfigurations) { mLoaderManager.doStop(); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { mLoaderManager.doRetain(); } } } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> performDestroyView() { ...... mCalled = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; onDestroyView(); ...... <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//生命周期依附上LoaderManager</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoaderManager != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mLoaderManager.doReportNextStart(); } }}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li><li style="box-sizing: border-box; padding: 0px 5px;">37</li><li style="box-sizing: border-box; padding: 0px 5px;">38</li><li style="box-sizing: border-box; padding: 0px 5px;">39</li><li style="box-sizing: border-box; padding: 0px 5px;">40</li><li style="box-sizing: border-box; padding: 0px 5px;">41</li><li style="box-sizing: border-box; padding: 0px 5px;">42</li><li style="box-sizing: border-box; padding: 0px 5px;">43</li><li style="box-sizing: border-box; padding: 0px 5px;">44</li><li style="box-sizing: border-box; padding: 0px 5px;">45</li><li style="box-sizing: border-box; padding: 0px 5px;">46</li><li style="box-sizing: border-box; padding: 0px 5px;">47</li><li style="box-sizing: border-box; padding: 0px 5px;">48</li><li style="box-sizing: border-box; padding: 0px 5px;">49</li><li style="box-sizing: border-box; padding: 0px 5px;">50</li><li style="box-sizing: border-box; padding: 0px 5px;">51</li><li style="box-sizing: border-box; padding: 0px 5px;">52</li><li style="box-sizing: border-box; padding: 0px 5px;">53</li><li style="box-sizing: border-box; padding: 0px 5px;">54</li><li style="box-sizing: border-box; padding: 0px 5px;">55</li><li style="box-sizing: border-box; padding: 0px 5px;">56</li><li style="box-sizing: border-box; padding: 0px 5px;">57</li><li style="box-sizing: border-box; padding: 0px 5px;">58</li><li style="box-sizing: border-box; padding: 0px 5px;">59</li><li style="box-sizing: border-box; padding: 0px 5px;">60</li><li style="box-sizing: border-box; padding: 0px 5px;">61</li><li style="box-sizing: border-box; padding: 0px 5px;">62</li><li style="box-sizing: border-box; padding: 0px 5px;">63</li><li style="box-sizing: border-box; padding: 0px 5px;">64</li><li style="box-sizing: border-box; padding: 0px 5px;">65</li><li style="box-sizing: border-box; padding: 0px 5px;">66</li><li style="box-sizing: border-box; padding: 0px 5px;">67</li><li style="box-sizing: border-box; padding: 0px 5px;">68</li><li style="box-sizing: border-box; padding: 0px 5px;">69</li><li style="box-sizing: border-box; padding: 0px 5px;">70</li><li style="box-sizing: border-box; padding: 0px 5px;">71</li><li style="box-sizing: border-box; padding: 0px 5px;">72</li><li style="box-sizing: border-box; padding: 0px 5px;">73</li><li style="box-sizing: border-box; padding: 0px 5px;">74</li><li style="box-sizing: border-box; padding: 0px 5px;">75</li><li style="box-sizing: border-box; padding: 0px 5px;">76</li><li style="box-sizing: border-box; padding: 0px 5px;">77</li><li style="box-sizing: border-box; padding: 0px 5px;">78</li><li style="box-sizing: border-box; padding: 0px 5px;">79</li><li style="box-sizing: border-box; padding: 0px 5px;">80</li><li style="box-sizing: border-box; padding: 0px 5px;">81</li><li style="box-sizing: border-box; padding: 0px 5px;">82</li><li style="box-sizing: border-box; padding: 0px 5px;">83</li><li style="box-sizing: border-box; padding: 0px 5px;">84</li><li style="box-sizing: border-box; padding: 0px 5px;">85</li><li style="box-sizing: border-box; padding: 0px 5px;">86</li><li style="box-sizing: border-box; padding: 0px 5px;">87</li><li style="box-sizing: border-box; padding: 0px 5px;">88</li><li style="box-sizing: border-box; padding: 0px 5px;">89</li><li style="box-sizing: border-box; padding: 0px 5px;">90</li><li style="box-sizing: border-box; padding: 0px 5px;">91</li><li style="box-sizing: border-box; padding: 0px 5px;">92</li><li style="box-sizing: border-box; padding: 0px 5px;">93</li><li style="box-sizing: border-box; padding: 0px 5px;">94</li><li style="box-sizing: border-box; padding: 0px 5px;">95</li><li style="box-sizing: border-box; padding: 0px 5px;">96</li></ul>从上面可以看出，Fragment在其生命周期内会控制LoaderManager（LoaderManager其实控制了Loader）的doStart、doDestroy等方法，也就是说我们在Fragment中只管通过getLoaderManager方法来获取LoaderManager实例，然后使用就行，别的Fragment都会帮我们处理OK的。
接下来看看Activity中的LoaderManager，如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">Activity</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ContextThemeWrapper</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">implements</span> ... {</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//mAllLoaderManagers保存了Activity与Fragment的所有LoaderManager</span> ArrayMap<String, LoaderManagerImpl> mAllLoaderManagers; LoaderManagerImpl mLoaderManager; ...... <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//Activity中获取LoaderManager实例的方法</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> LoaderManager <span class="hljs-title" style="box-sizing: border-box;">getLoaderManager</span>() { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//可以看见，一个Activity只有一个LoaderManager</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoaderManager != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mLoaderManager; } mCheckedForLoaderManager = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//咦？这不就是上面Fragment的getLoaderManager中调运的那个activity中的getLoaderManager吗，只是和这里的参数不一样而已</span> mLoaderManager = getLoaderManager(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"(root)"</span>, mLoadersStarted, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mLoaderManager; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//Activity与Fragment获取LoaderManager实例的真正方法！！</span> LoaderManagerImpl getLoaderManager(String who, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> started, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> create) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//可见一个Activity维护一个mAllLoaderManagers的MAP</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mAllLoaderManagers == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mAllLoaderManagers = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> ArrayMap<String, LoaderManagerImpl>(); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//尝试从缓存mAllLoaderManagers的MAP中获取已经实例化的LoaderManager实例</span> LoaderManagerImpl lm = mAllLoaderManagers.get(who); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (lm == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (create) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//如果没有找到并且需要实例化create（切记这个create参数是很重要的），就调运LoaderManagerImpl构造方法实例化一个LoaderManager对象，然后存入缓存mAllLoaderManagers的MAP中</span> lm = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> LoaderManagerImpl(who, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>, started); mAllLoaderManagers.put(who, lm); } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { lm.updateActivity(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> lm; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> invalidateFragment(String who) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mAllLoaderManagers != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { LoaderManagerImpl lm = mAllLoaderManagers.get(who); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (lm != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> && !lm.mRetaining) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//生命周期依附上LoaderManager</span> lm.doDestroy(); mAllLoaderManagers.remove(who); } } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> performStop() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoadersStarted) { mLoadersStarted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//生命周期依附上LoaderManager</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoaderManager != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//mChangingConfigurations表示如果当前发生了配置变化则为true，否则为false！！！！！！！重点，Loader特性之一</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!mChangingConfigurations) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//当前Activity的stop不是由配置变化引起则直接调用LoaderManager的doStop()方法！！！！！！</span> mLoaderManager.doStop(); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//当前Activity配置变化，所以需要保存当前的loaderManager，在Activity恢复时恢复这个LoaderManager！！！！！！</span> mLoaderManager.doRetain(); } } } ...... } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> performDestroy() { ...... onDestroy(); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//生命周期依附上LoaderManager</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoaderManager != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mLoaderManager.doDestroy(); } ...... } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onCreate</span>(@Nullable Bundle savedInstanceState) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLastNonConfigurationInstances != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//从mLastNonConfigurationInstances中恢复mAllLoaderManagers（mLastNonConfigurationInstances是从onAttach中恢复的），Activity配置变化时会走这里！！！！</span> mAllLoaderManagers = mLastNonConfigurationInstances.loaders; } ...... mCalled = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> performStart() { ...... <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mAllLoaderManagers != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> N = mAllLoaderManagers.size(); LoaderManagerImpl loaders[] = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> LoaderManagerImpl[N]; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">for</span> (<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> i=N-<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">1</span>; i>=<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>; i--) { loaders[i] = mAllLoaderManagers.valueAt(i); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//生命周期依附上LoaderManager</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">for</span> (<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> i=<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>; i<N; i++) { LoaderManagerImpl lm = loaders[i]; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//调用LoaderManager.finishRetain()以及doReportStart()方法来恢复LoaderManager的状态！！！！！</span> lm.finishRetain(); lm.doReportStart(); } } mActivityTransitionState.enterReady(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//该方法会被ActivityThread类调用，且调运时机早于performDestroy()方法！！！！！！</span> NonConfigurationInstances retainNonConfigurationInstances() { ...... NonConfigurationInstances nci = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> NonConfigurationInstances(); ...... <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//配置变化时保存mAllLoaderManagers！！！！！！</span> nci.loaders = mAllLoaderManagers; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> nci; }}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li><li style="box-sizing: border-box; padding: 0px 5px;">37</li><li style="box-sizing: border-box; padding: 0px 5px;">38</li><li style="box-sizing: border-box; padding: 0px 5px;">39</li><li style="box-sizing: border-box; padding: 0px 5px;">40</li><li style="box-sizing: border-box; padding: 0px 5px;">41</li><li style="box-sizing: border-box; padding: 0px 5px;">42</li><li style="box-sizing: border-box; padding: 0px 5px;">43</li><li style="box-sizing: border-box; padding: 0px 5px;">44</li><li style="box-sizing: border-box; padding: 0px 5px;">45</li><li style="box-sizing: border-box; padding: 0px 5px;">46</li><li style="box-sizing: border-box; padding: 0px 5px;">47</li><li style="box-sizing: border-box; padding: 0px 5px;">48</li><li style="box-sizing: border-box; padding: 0px 5px;">49</li><li style="box-sizing: border-box; padding: 0px 5px;">50</li><li style="box-sizing: border-box; padding: 0px 5px;">51</li><li style="box-sizing: border-box; padding: 0px 5px;">52</li><li style="box-sizing: border-box; padding: 0px 5px;">53</li><li style="box-sizing: border-box; padding: 0px 5px;">54</li><li style="box-sizing: border-box; padding: 0px 5px;">55</li><li style="box-sizing: border-box; padding: 0px 5px;">56</li><li style="box-sizing: border-box; padding: 0px 5px;">57</li><li style="box-sizing: border-box; padding: 0px 5px;">58</li><li style="box-sizing: border-box; padding: 0px 5px;">59</li><li style="box-sizing: border-box; padding: 0px 5px;">60</li><li style="box-sizing: border-box; padding: 0px 5px;">61</li><li style="box-sizing: border-box; padding: 0px 5px;">62</li><li style="box-sizing: border-box; padding: 0px 5px;">63</li><li style="box-sizing: border-box; padding: 0px 5px;">64</li><li style="box-sizing: border-box; padding: 0px 5px;">65</li><li style="box-sizing: border-box; padding: 0px 5px;">66</li><li style="box-sizing: border-box; padding: 0px 5px;">67</li><li style="box-sizing: border-box; padding: 0px 5px;">68</li><li style="box-sizing: border-box; padding: 0px 5px;">69</li><li style="box-sizing: border-box; padding: 0px 5px;">70</li><li style="box-sizing: border-box; padding: 0px 5px;">71</li><li style="box-sizing: border-box; padding: 0px 5px;">72</li><li style="box-sizing: border-box; padding: 0px 5px;">73</li><li style="box-sizing: border-box; padding: 0px 5px;">74</li><li style="box-sizing: border-box; padding: 0px 5px;">75</li><li style="box-sizing: border-box; padding: 0px 5px;">76</li><li style="box-sizing: border-box; padding: 0px 5px;">77</li><li style="box-sizing: border-box; padding: 0px 5px;">78</li><li style="box-sizing: border-box; padding: 0px 5px;">79</li><li style="box-sizing: border-box; padding: 0px 5px;">80</li><li style="box-sizing: border-box; padding: 0px 5px;">81</li><li style="box-sizing: border-box; padding: 0px 5px;">82</li><li style="box-sizing: border-box; padding: 0px 5px;">83</li><li style="box-sizing: border-box; padding: 0px 5px;">84</li><li style="box-sizing: border-box; padding: 0px 5px;">85</li><li style="box-sizing: border-box; padding: 0px 5px;">86</li><li style="box-sizing: border-box; padding: 0px 5px;">87</li><li style="box-sizing: border-box; padding: 0px 5px;">88</li><li style="box-sizing: border-box; padding: 0px 5px;">89</li><li style="box-sizing: border-box; padding: 0px 5px;">90</li><li style="box-sizing: border-box; padding: 0px 5px;">91</li><li style="box-sizing: border-box; padding: 0px 5px;">92</li><li style="box-sizing: border-box; padding: 0px 5px;">93</li><li style="box-sizing: border-box; padding: 0px 5px;">94</li><li style="box-sizing: border-box; padding: 0px 5px;">95</li><li style="box-sizing: border-box; padding: 0px 5px;">96</li><li style="box-sizing: border-box; padding: 0px 5px;">97</li><li style="box-sizing: border-box; padding: 0px 5px;">98</li><li style="box-sizing: border-box; padding: 0px 5px;">99</li><li style="box-sizing: border-box; padding: 0px 5px;">100</li><li style="box-sizing: border-box; padding: 0px 5px;">101</li><li style="box-sizing: border-box; padding: 0px 5px;">102</li><li style="box-sizing: border-box; padding: 0px 5px;">103</li><li style="box-sizing: border-box; padding: 0px 5px;">104</li><li style="box-sizing: border-box; padding: 0px 5px;">105</li><li style="box-sizing: border-box; padding: 0px 5px;">106</li><li style="box-sizing: border-box; padding: 0px 5px;">107</li><li style="box-sizing: border-box; padding: 0px 5px;">108</li><li style="box-sizing: border-box; padding: 0px 5px;">109</li><li style="box-sizing: border-box; padding: 0px 5px;">110</li><li style="box-sizing: border-box; padding: 0px 5px;">111</li><li style="box-sizing: border-box; padding: 0px 5px;">112</li><li style="box-sizing: border-box; padding: 0px 5px;">113</li></ul>通过上面的分析可以发现，Activity其实真正的管理了Activity及Fragment的LoaderManager（Fragment也会管理一部分自己LoaderManager的周期），而LoaderManager又管理了Loader，可以发现他们各自的管理范围都是十分的清晰明了的。
3-2 LoadManager及其实现类LoadManagerImpl的浅析
上面分析Activity及Fragment中获取LoaderManager实例时已经知道，我们获取的LoaderManager实例其实就是LoaderManagerImpl对象，而LoaderManagerImpl又是LoaderManager类的子类，所以接下来我们来分析这两个父子类。
先看下抽象父类LoaderManager，如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">abstract</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">LoaderManager</span> {</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//LoaderManager的回调接口定义</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">interface</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">LoaderCallbacks</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">D</span>> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> Loader<D> <span class="hljs-title" style="box-sizing: border-box;">onCreateLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, Bundle args); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoadFinished</span>(Loader<D> loader, D data); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoaderReset</span>(Loader<D> loader); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//下面这些方法没必要再细说了，上面介绍过的</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">abstract</span> <D> Loader<D> <span class="hljs-title" style="box-sizing: border-box;">initLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, Bundle args, LoaderManager.LoaderCallbacks<D> callback); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">abstract</span> <D> Loader<D> <span class="hljs-title" style="box-sizing: border-box;">restartLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, Bundle args, LoaderManager.LoaderCallbacks<D> callback); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//会触发回调的onLoaderReset方法</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">abstract</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">destroyLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">abstract</span> <D> Loader<D> <span class="hljs-title" style="box-sizing: border-box;">getLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">abstract</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">dump</span>(String prefix, FileDescriptor fd, PrintWriter writer, String[] args); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">enableDebugLogging</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> enabled) { LoaderManagerImpl.DEBUG = enabled; }}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li></ul>可以看见LoaderManager抽象类只是定义了一些规范接口而已，那么接着我们看下抽象类LoaderManager的实现类LoaderManagerImpl，如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;">class LoaderManagerImpl extends LoaderManager { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> String TAG = <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"LoaderManager"</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> DEBUG = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//保存当前存活的Loader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> SparseArray<LoaderInfo> mLoaders = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> SparseArray<LoaderInfo>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//保存已经运行完的Loader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> SparseArray<LoaderInfo> mInactiveLoaders = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> SparseArray<LoaderInfo>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> String mWho; Activity mActivity; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mStarted; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mRetaining; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mRetainingStarted; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//是否正在创建Loader，多线程中同时调运创建会导致异常</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mCreatingLoader; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//Loader的封装类</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> class LoaderInfo implements Loader.OnLoadCompleteListener<Object>, Loader.OnLoadCanceledListener<Object> { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> mId; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> Bundle mArgs; LoaderManager.LoaderCallbacks<Object> mCallbacks; Loader<Object> mLoader; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mHaveData; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mDeliveredData; Object mData; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mStarted; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//mRetaining标记Activity配置变化时保持当前Loader，不用销毁；和上面分析Activity的LoaderManager的retainNonConfigurationInstances方法关联！！！！！！</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mRetaining; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mRetainingStarted; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mReportNextStart; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mDestroyed; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mListenerRegistered; LoaderInfo mPendingLoader; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//LoaderInfo构造方法</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">LoaderInfo</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, Bundle args, LoaderManager.LoaderCallbacks<Object> callbacks) { mId = id; mArgs = args; mCallbacks = callbacks; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//启动一个Loader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> start() { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//配置改变恢复则不用启动，用原来的</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mRetaining && mRetainingStarted) { mStarted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span>; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//如果已经启动，则不用再restart了</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mStarted) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span>; } mStarted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//如果当前封装中mLoader为空并且通过构造方法的mCallbacks不为空则回调onCreateLoader方法创建Loader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoader == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> && mCallbacks != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mLoader = mCallbacks.onCreateLoader(mId, mArgs); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoader != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoader.getClass().isMemberClass() && !Modifier.isStatic(mLoader.getClass().getModifiers())) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//如果当前创建的Loader对象是一个非静态内部类则抛异常！！！！！！</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> IllegalArgumentException( <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Object returned from onCreateLoader must not be a non-static inner member class: "</span> + mLoader); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!mListenerRegistered) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//注册Loader的监听方法</span> mLoader.registerListener(mId, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); mLoader.registerOnLoadCanceledListener(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); mListenerRegistered = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//调运Loader的startLoading方法</span> mLoader.startLoading(); } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//Activity的配置改变时进行标志位的设置，以便可以保存，配合上面Activity的分析！！！！！！</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> retain() { mRetaining = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; ...... } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//Activity配置变化后重启后如果有数据则通知回调方法，配合上面Activity的分析！！！！！！</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> finishRetain() { ...... <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mStarted && mHaveData && !mReportNextStart) { callOnLoadFinished(mLoader, mData); } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//配合上面Activity的分析！！！！！！</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> reportStart() { ...... } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//停止Loader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> stop() { mStarted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!mRetaining) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//如果不是Activity配置变化，即不用保存则注销掉这些回调</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoader != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> && mListenerRegistered) { ...... } } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//取消掉Loader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> cancel() { ...... } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//销毁掉Loader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> destroy() { ...... <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCallbacks != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> && mLoader != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> && mHaveData && needReset) { ...... <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">try</span> { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//在destroy时如果有数据存在则调用callback的onLoaderReset方法！！！！！！</span> mCallbacks.onLoaderReset(mLoader); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">finally</span> { ...... } } ...... <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLoader != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//注销监听方法</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mListenerRegistered) { ...... } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//close Cursor等重置操作</span> mLoader.reset(); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mPendingLoader != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mPendingLoader.destroy(); } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//Loader被取消时回调该方法</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoadCanceled</span>(Loader<Object> loader) { ...... LoaderInfo pending = mPendingLoader; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//执行最新的Loader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (pending != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mPendingLoader = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; mLoaders.put(mId, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>); destroy(); installLoader(pending); } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//加载完成时回调</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoadComplete</span>(Loader<Object> loader, Object data) { ...... <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//执行最新的Loader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (pending != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mPendingLoader = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; mLoaders.put(mId, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>); destroy(); installLoader(pending); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span>; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mData != data || !mHaveData) { mData = data; mHaveData = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mStarted) { callOnLoadFinished(loader, data); } } ...... } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//调用onLoadFinished</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> callOnLoadFinished(Loader<Object> loader, Object data) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCallbacks != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { ...... <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">try</span> { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//回调onLoadFinished方法</span> mCallbacks.onLoadFinished(loader, data); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">finally</span> { ...... } mDeliveredData = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//！！！！！！真正LoaderManagerImpl的构造方法</span> LoaderManagerImpl(String who, Activity activity, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> started) { mWho = who; mActivity = activity; mStarted = started; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//更新当前Activity引用</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> updateActivity(Activity activity) { mActivity = activity; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//私有的创建Loader方法</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> LoaderInfo <span class="hljs-title" style="box-sizing: border-box;">createLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, Bundle args, LoaderManager.LoaderCallbacks<Object> callback) { LoaderInfo info = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> LoaderInfo(id, args, (LoaderManager.LoaderCallbacks<Object>)callback); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//回调callback的onCreateLoader方法得到Loader对象</span> Loader<Object> loader = callback.onCreateLoader(id, args); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//把得到的Loader对象包装成LoaderInfo对象</span> info.mLoader = (Loader<Object>)loader; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> info; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//包装了创建Loader与install方法，并将mCreatingLoader标记置位</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> LoaderInfo <span class="hljs-title" style="box-sizing: border-box;">createAndInstallLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, Bundle args, LoaderManager.LoaderCallbacks<Object> callback) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">try</span> { mCreatingLoader = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//调运上面的私有创建方法创建LoaderInfo对象</span> LoaderInfo info = createLoader(id, args, callback); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//把创建的LoaderInfo对象传入installLoader方法</span> installLoader(info); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> info; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">finally</span> { mCreatingLoader = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> installLoader(LoaderInfo info) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//将创建的LoaderInfo对象存入mLoaders的Map中</span> mLoaders.put(info.mId, info); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mStarted) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//如果Activity已经started，则启动LoaderInfo的start方法</span> info.start(); } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//public的方法，创建一个Loader，前面介绍过的</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@SuppressWarnings</span>(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"unchecked"</span>) <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <D> Loader<D> <span class="hljs-title" style="box-sizing: border-box;">initLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, Bundle args, LoaderManager.LoaderCallbacks<D> callback) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//如果多线程中正在有创建的则抛出异常（写代码要注意这种情况，尤其是跑Monkey容易抛出，解决办法就是保证都在统一线程中执行！！！！！！）</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCreatingLoader) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> IllegalStateException(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Called while creating a loader"</span>); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//从现有的Map中尝试获取指定ID的LoaderInfo对象</span> LoaderInfo info = mLoaders.get(id); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (info == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//发现不存在就调运上面的createAndInstallLoader创建一个</span> info = createAndInstallLoader(id, args, (LoaderManager.LoaderCallbacks<Object>)callback); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//否则还用当前的Loader，只是重新赋值了callBack而已</span> info.mCallbacks = (LoaderManager.LoaderCallbacks<Object>)callback; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (info.mHaveData && mStarted) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//已经有数据，直接调运LoaderInfo的callOnLoadFinished</span> info.callOnLoadFinished(info.mLoader, info.mData); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//返回Loader对象</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> (Loader<D>)info.mLoader; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//重新创造Loader，前面介绍过的</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@SuppressWarnings</span>(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"unchecked"</span>) <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <D> Loader<D> <span class="hljs-title" style="box-sizing: border-box;">restartLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, Bundle args, LoaderManager.LoaderCallbacks<D> callback) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCreatingLoader) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//如果多线程中正在有创建的则抛出异常（写代码要注意这种情况，尤其是跑Monkey容易抛出，解决办法就是保证都在统一线程中执行！！！！！！）</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> IllegalStateException(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Called while creating a loader"</span>); } LoaderInfo info = mLoaders.get(id); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (info != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { LoaderInfo inactive = mInactiveLoaders.get(id); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (inactive != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (info.mHaveData) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//发现是已经运行完的Loader且已经存在的Loader有数据则destroy掉运行完的Loader</span> inactive.mDeliveredData = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; inactive.destroy(); info.mLoader.abandon(); mInactiveLoaders.put(id, info); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!info.mStarted) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//有相同id的Loader还没start则destory掉</span> mLoaders.put(id, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>); info.destroy(); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//有一个相同id的Loader正在加载数据，但是还没加载完，调用它的cancel()方法通知取消加载</span> info.cancel(); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (info.mPendingLoader != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { info.mPendingLoader.destroy(); info.mPendingLoader = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//创建一个指定id的Loader同时赋给mPendingLoader，因为这个时候已经有一个Loader正在加载数据，而且我们已经调用了其cancel()方法来通知取消加载</span> info.mPendingLoader = createLoader(id, args, (LoaderManager.LoaderCallbacks<Object>)callback); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//返回创建的Loader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> (Loader<D>)info.mPendingLoader.mLoader; } } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//终止已存在的Loader</span> info.mLoader.abandon(); mInactiveLoaders.put(id, info); } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//重新创建Loader返回</span> info = createAndInstallLoader(id, args, (LoaderManager.LoaderCallbacks<Object>)callback); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> (Loader<D>)info.mLoader; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//销毁指定id的Loader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">destroyLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCreatingLoader) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> IllegalStateException(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Called while creating a loader"</span>); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//不解释，单纯的destory</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> idx = mLoaders.indexOfKey(id); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (idx >= <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>) { LoaderInfo info = mLoaders.valueAt(idx); mLoaders.removeAt(idx); info.destroy(); } idx = mInactiveLoaders.indexOfKey(id); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (idx >= <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>) { LoaderInfo info = mInactiveLoaders.valueAt(idx); mInactiveLoaders.removeAt(idx); info.destroy(); } ...... } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//获取指定id的Loader对象</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@SuppressWarnings</span>(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"unchecked"</span>) <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <D> Loader<D> <span class="hljs-title" style="box-sizing: border-box;">getLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCreatingLoader) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> IllegalStateException(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Called while creating a loader"</span>); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//优先获取LoaderInfo中的mPendingLoader</span> LoaderInfo loaderInfo = mLoaders.get(id); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (loaderInfo != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (loaderInfo.mPendingLoader != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> (Loader<D>)loaderInfo.mPendingLoader.mLoader; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> (Loader<D>)loaderInfo.mLoader; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; } ......}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; 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padding: 0px 5px;">106</li><li style="box-sizing: border-box; padding: 0px 5px;">107</li><li style="box-sizing: border-box; padding: 0px 5px;">108</li><li style="box-sizing: border-box; padding: 0px 5px;">109</li><li style="box-sizing: border-box; padding: 0px 5px;">110</li><li style="box-sizing: border-box; padding: 0px 5px;">111</li><li style="box-sizing: border-box; padding: 0px 5px;">112</li><li style="box-sizing: border-box; padding: 0px 5px;">113</li><li style="box-sizing: border-box; padding: 0px 5px;">114</li><li style="box-sizing: border-box; padding: 0px 5px;">115</li><li style="box-sizing: border-box; padding: 0px 5px;">116</li><li style="box-sizing: border-box; padding: 0px 5px;">117</li><li style="box-sizing: border-box; padding: 0px 5px;">118</li><li style="box-sizing: border-box; padding: 0px 5px;">119</li><li style="box-sizing: border-box; padding: 0px 5px;">120</li><li style="box-sizing: border-box; padding: 0px 5px;">121</li><li style="box-sizing: border-box; padding: 0px 5px;">122</li><li style="box-sizing: border-box; padding: 0px 5px;">123</li><li style="box-sizing: border-box; padding: 0px 5px;">124</li><li style="box-sizing: border-box; padding: 0px 5px;">125</li><li style="box-sizing: border-box; padding: 0px 5px;">126</li><li style="box-sizing: border-box; padding: 0px 5px;">127</li><li style="box-sizing: border-box; padding: 0px 5px;">128</li><li style="box-sizing: border-box; padding: 0px 5px;">129</li><li style="box-sizing: border-box; padding: 0px 5px;">130</li><li style="box-sizing: border-box; padding: 0px 5px;">131</li><li style="box-sizing: border-box; padding: 0px 5px;">132</li><li style="box-sizing: border-box; padding: 0px 5px;">133</li><li style="box-sizing: border-box; padding: 0px 5px;">134</li><li style="box-sizing: border-box; padding: 0px 5px;">135</li><li style="box-sizing: border-box; padding: 0px 5px;">136</li><li style="box-sizing: border-box; padding: 0px 5px;">137</li><li style="box-sizing: border-box; padding: 0px 5px;">138</li><li style="box-sizing: border-box; padding: 0px 5px;">139</li><li style="box-sizing: border-box; padding: 0px 5px;">140</li><li style="box-sizing: border-box; padding: 0px 5px;">141</li><li style="box-sizing: border-box; padding: 0px 5px;">142</li><li style="box-sizing: border-box; padding: 0px 5px;">143</li><li style="box-sizing: border-box; padding: 0px 5px;">144</li><li style="box-sizing: border-box; padding: 0px 5px;">145</li><li style="box-sizing: border-box; padding: 0px 5px;">146</li><li style="box-sizing: border-box; padding: 0px 5px;">147</li><li style="box-sizing: border-box; padding: 0px 5px;">148</li><li style="box-sizing: border-box; padding: 0px 5px;">149</li><li style="box-sizing: border-box; padding: 0px 5px;">150</li><li style="box-sizing: border-box; padding: 0px 5px;">151</li><li style="box-sizing: border-box; padding: 0px 5px;">152</li><li style="box-sizing: border-box; padding: 0px 5px;">153</li><li style="box-sizing: border-box; padding: 0px 5px;">154</li><li style="box-sizing: border-box; padding: 0px 5px;">155</li><li style="box-sizing: border-box; padding: 0px 5px;">156</li><li style="box-sizing: border-box; padding: 0px 5px;">157</li><li style="box-sizing: border-box; padding: 0px 5px;">158</li><li style="box-sizing: border-box; padding: 0px 5px;">159</li><li style="box-sizing: border-box; padding: 0px 5px;">160</li><li style="box-sizing: border-box; padding: 0px 5px;">161</li><li style="box-sizing: border-box; padding: 0px 5px;">162</li><li style="box-sizing: border-box; padding: 0px 5px;">163</li><li style="box-sizing: border-box; padding: 0px 5px;">164</li><li style="box-sizing: border-box; padding: 0px 5px;">165</li><li style="box-sizing: border-box; padding: 0px 5px;">166</li><li style="box-sizing: border-box; padding: 0px 5px;">167</li><li style="box-sizing: border-box; padding: 0px 5px;">168</li><li style="box-sizing: border-box; padding: 0px 5px;">169</li><li style="box-sizing: border-box; padding: 0px 5px;">170</li><li style="box-sizing: border-box; padding: 0px 5px;">171</li><li style="box-sizing: border-box; padding: 0px 5px;">172</li><li style="box-sizing: border-box; padding: 0px 5px;">173</li><li style="box-sizing: border-box; padding: 0px 5px;">174</li><li style="box-sizing: border-box; padding: 0px 5px;">175</li><li style="box-sizing: border-box; padding: 0px 5px;">176</li><li style="box-sizing: border-box; padding: 0px 5px;">177</li><li style="box-sizing: border-box; padding: 0px 5px;">178</li><li style="box-sizing: border-box; padding: 0px 5px;">179</li><li style="box-sizing: border-box; padding: 0px 5px;">180</li><li style="box-sizing: border-box; padding: 0px 5px;">181</li><li style="box-sizing: border-box; padding: 0px 5px;">182</li><li style="box-sizing: border-box; padding: 0px 5px;">183</li><li style="box-sizing: border-box; padding: 0px 5px;">184</li><li style="box-sizing: border-box; padding: 0px 5px;">185</li><li style="box-sizing: border-box; padding: 0px 5px;">186</li><li style="box-sizing: border-box; padding: 0px 5px;">187</li><li style="box-sizing: border-box; padding: 0px 5px;">188</li><li style="box-sizing: border-box; padding: 0px 5px;">189</li><li style="box-sizing: border-box; padding: 0px 5px;">190</li><li style="box-sizing: border-box; padding: 0px 5px;">191</li><li style="box-sizing: border-box; padding: 0px 5px;">192</li><li style="box-sizing: border-box; padding: 0px 5px;">193</li><li style="box-sizing: border-box; padding: 0px 5px;">194</li><li style="box-sizing: border-box; padding: 0px 5px;">195</li><li style="box-sizing: border-box; padding: 0px 5px;">196</li><li style="box-sizing: border-box; padding: 0px 5px;">197</li><li style="box-sizing: border-box; padding: 0px 5px;">198</li><li style="box-sizing: border-box; padding: 0px 5px;">199</li><li style="box-sizing: border-box; padding: 0px 5px;">200</li><li style="box-sizing: border-box; padding: 0px 5px;">201</li><li style="box-sizing: border-box; padding: 0px 5px;">202</li><li style="box-sizing: border-box; padding: 0px 5px;">203</li><li style="box-sizing: border-box; padding: 0px 5px;">204</li><li style="box-sizing: border-box; padding: 0px 5px;">205</li><li style="box-sizing: border-box; padding: 0px 5px;">206</li><li style="box-sizing: border-box; padding: 0px 5px;">207</li><li style="box-sizing: border-box; padding: 0px 5px;">208</li><li style="box-sizing: border-box; padding: 0px 5px;">209</li><li style="box-sizing: border-box; padding: 0px 5px;">210</li><li style="box-sizing: border-box; padding: 0px 5px;">211</li><li style="box-sizing: border-box; padding: 0px 5px;">212</li><li style="box-sizing: border-box; padding: 0px 5px;">213</li><li style="box-sizing: border-box; padding: 0px 5px;">214</li><li style="box-sizing: border-box; padding: 0px 5px;">215</li><li style="box-sizing: border-box; padding: 0px 5px;">216</li><li style="box-sizing: border-box; padding: 0px 5px;">217</li><li style="box-sizing: border-box; padding: 0px 5px;">218</li><li style="box-sizing: border-box; padding: 0px 5px;">219</li><li style="box-sizing: border-box; padding: 0px 5px;">220</li><li style="box-sizing: border-box; padding: 0px 5px;">221</li><li style="box-sizing: border-box; padding: 0px 5px;">222</li><li style="box-sizing: border-box; padding: 0px 5px;">223</li><li style="box-sizing: border-box; padding: 0px 5px;">224</li><li style="box-sizing: border-box; padding: 0px 5px;">225</li><li style="box-sizing: border-box; padding: 0px 5px;">226</li><li style="box-sizing: border-box; padding: 0px 5px;">227</li><li style="box-sizing: border-box; padding: 0px 5px;">228</li><li style="box-sizing: border-box; padding: 0px 5px;">229</li><li style="box-sizing: border-box; padding: 0px 5px;">230</li><li style="box-sizing: border-box; padding: 0px 5px;">231</li><li style="box-sizing: border-box; padding: 0px 5px;">232</li><li style="box-sizing: border-box; padding: 0px 5px;">233</li><li style="box-sizing: border-box; padding: 0px 5px;">234</li><li style="box-sizing: border-box; padding: 0px 5px;">235</li><li style="box-sizing: border-box; padding: 0px 5px;">236</li><li style="box-sizing: border-box; padding: 0px 5px;">237</li><li style="box-sizing: border-box; padding: 0px 5px;">238</li><li style="box-sizing: border-box; padding: 0px 5px;">239</li><li style="box-sizing: border-box; padding: 0px 5px;">240</li><li style="box-sizing: border-box; padding: 0px 5px;">241</li><li style="box-sizing: border-box; padding: 0px 5px;">242</li><li style="box-sizing: border-box; padding: 0px 5px;">243</li><li style="box-sizing: border-box; padding: 0px 5px;">244</li><li style="box-sizing: border-box; padding: 0px 5px;">245</li><li style="box-sizing: border-box; padding: 0px 5px;">246</li><li style="box-sizing: border-box; padding: 0px 5px;">247</li><li style="box-sizing: border-box; padding: 0px 5px;">248</li><li style="box-sizing: border-box; padding: 0px 5px;">249</li><li style="box-sizing: border-box; padding: 0px 5px;">250</li><li style="box-sizing: border-box; padding: 0px 5px;">251</li><li style="box-sizing: border-box; padding: 0px 5px;">252</li><li style="box-sizing: border-box; padding: 0px 5px;">253</li><li style="box-sizing: border-box; padding: 0px 5px;">254</li><li style="box-sizing: border-box; padding: 0px 5px;">255</li><li style="box-sizing: border-box; padding: 0px 5px;">256</li><li style="box-sizing: border-box; padding: 0px 5px;">257</li><li style="box-sizing: border-box; padding: 0px 5px;">258</li><li style="box-sizing: border-box; padding: 0px 5px;">259</li><li style="box-sizing: border-box; padding: 0px 5px;">260</li><li style="box-sizing: border-box; padding: 0px 5px;">261</li><li style="box-sizing: border-box; padding: 0px 5px;">262</li><li style="box-sizing: border-box; padding: 0px 5px;">263</li><li style="box-sizing: border-box; padding: 0px 5px;">264</li><li style="box-sizing: border-box; padding: 0px 5px;">265</li><li style="box-sizing: border-box; padding: 0px 5px;">266</li><li style="box-sizing: border-box; padding: 0px 5px;">267</li><li style="box-sizing: border-box; padding: 0px 5px;">268</li><li style="box-sizing: border-box; padding: 0px 5px;">269</li><li style="box-sizing: border-box; padding: 0px 5px;">270</li><li style="box-sizing: border-box; padding: 0px 5px;">271</li><li style="box-sizing: border-box; padding: 0px 5px;">272</li><li style="box-sizing: border-box; padding: 0px 5px;">273</li><li style="box-sizing: border-box; padding: 0px 5px;">274</li><li style="box-sizing: border-box; padding: 0px 5px;">275</li><li style="box-sizing: border-box; padding: 0px 5px;">276</li><li style="box-sizing: border-box; padding: 0px 5px;">277</li><li style="box-sizing: border-box; padding: 0px 5px;">278</li><li style="box-sizing: border-box; padding: 0px 5px;">279</li><li style="box-sizing: border-box; padding: 0px 5px;">280</li><li style="box-sizing: border-box; padding: 0px 5px;">281</li><li style="box-sizing: border-box; padding: 0px 5px;">282</li><li style="box-sizing: border-box; padding: 0px 5px;">283</li><li style="box-sizing: border-box; padding: 0px 5px;">284</li><li style="box-sizing: border-box; padding: 0px 5px;">285</li><li style="box-sizing: border-box; padding: 0px 5px;">286</li><li style="box-sizing: border-box; padding: 0px 5px;">287</li><li style="box-sizing: border-box; padding: 0px 5px;">288</li><li style="box-sizing: border-box; padding: 0px 5px;">289</li><li style="box-sizing: border-box; padding: 0px 5px;">290</li><li style="box-sizing: border-box; padding: 0px 5px;">291</li><li style="box-sizing: border-box; padding: 0px 5px;">292</li><li style="box-sizing: border-box; padding: 0px 5px;">293</li><li style="box-sizing: border-box; padding: 0px 5px;">294</li><li style="box-sizing: border-box; padding: 0px 5px;">295</li><li style="box-sizing: border-box; padding: 0px 5px;">296</li><li style="box-sizing: border-box; padding: 0px 5px;">297</li><li style="box-sizing: border-box; padding: 0px 5px;">298</li><li style="box-sizing: border-box; padding: 0px 5px;">299</li><li style="box-sizing: border-box; padding: 0px 5px;">300</li><li style="box-sizing: border-box; padding: 0px 5px;">301</li><li style="box-sizing: border-box; padding: 0px 5px;">302</li><li style="box-sizing: border-box; padding: 0px 5px;">303</li><li style="box-sizing: border-box; padding: 0px 5px;">304</li><li style="box-sizing: border-box; padding: 0px 5px;">305</li><li style="box-sizing: border-box; padding: 0px 5px;">306</li><li style="box-sizing: border-box; padding: 0px 5px;">307</li><li style="box-sizing: border-box; padding: 0px 5px;">308</li><li style="box-sizing: border-box; padding: 0px 5px;">309</li><li style="box-sizing: border-box; padding: 0px 5px;">310</li><li style="box-sizing: border-box; padding: 0px 5px;">311</li><li style="box-sizing: border-box; padding: 0px 5px;">312</li><li style="box-sizing: border-box; padding: 0px 5px;">313</li><li style="box-sizing: border-box; padding: 0px 5px;">314</li><li style="box-sizing: border-box; padding: 0px 5px;">315</li><li style="box-sizing: border-box; padding: 0px 5px;">316</li><li style="box-sizing: border-box; padding: 0px 5px;">317</li><li style="box-sizing: border-box; padding: 0px 5px;">318</li><li style="box-sizing: border-box; padding: 0px 5px;">319</li><li style="box-sizing: border-box; padding: 0px 5px;">320</li><li style="box-sizing: border-box; padding: 0px 5px;">321</li><li style="box-sizing: border-box; padding: 0px 5px;">322</li><li style="box-sizing: border-box; padding: 0px 5px;">323</li><li style="box-sizing: border-box; padding: 0px 5px;">324</li><li style="box-sizing: border-box; padding: 0px 5px;">325</li><li style="box-sizing: border-box; padding: 0px 5px;">326</li><li style="box-sizing: border-box; padding: 0px 5px;">327</li><li style="box-sizing: border-box; padding: 0px 5px;">328</li><li style="box-sizing: border-box; padding: 0px 5px;">329</li><li style="box-sizing: border-box; padding: 0px 5px;">330</li><li style="box-sizing: border-box; padding: 0px 5px;">331</li><li style="box-sizing: border-box; padding: 0px 5px;">332</li><li style="box-sizing: border-box; padding: 0px 5px;">333</li><li style="box-sizing: border-box; padding: 0px 5px;">334</li><li style="box-sizing: border-box; padding: 0px 5px;">335</li><li style="box-sizing: border-box; padding: 0px 5px;">336</li><li style="box-sizing: border-box; padding: 0px 5px;">337</li><li style="box-sizing: border-box; padding: 0px 5px;">338</li><li style="box-sizing: border-box; padding: 0px 5px;">339</li><li style="box-sizing: border-box; padding: 0px 5px;">340</li><li style="box-sizing: border-box; padding: 0px 5px;">341</li><li style="box-sizing: border-box; padding: 0px 5px;">342</li></ul>我勒个去！好长，好累！通过上面粗略的分析你会发现和我们上面基础实例介绍LoaderManager的方法时描述的一样，每个方法都有自己的特点，发挥着各自的作用，LoaderManager的实质是将Loader对象转换为LoaderInfo来进行管理，也就是管理了所有的Loader对象。
3-3 Loader及其实现类的浅析
上面分析了Activity及Fragment管理了LoaderManager的相关方法，LoaderManager管理了Loader的相关方法，那么接下来我们就来看看这个被管理的终极目标Loader是咋回事，还有他的子类咋回事。
先来看看我画的一张关系图，如下：
我去，这图现在看可能有些吓人，我们还是先来慢慢分析一下再说吧。
3-3-1 Loader基类源码浅析
我们先来看看这个Loader基类吧，该类核心方法及内部类结构图如下：
代码分析如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">Loader</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">D</span>> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> mId; OnLoadCompleteListener<D> mListener; OnLoadCanceledListener<D> mOnLoadCanceledListener; Context mContext; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mStarted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mAbandoned = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mReset = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mContentChanged = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mProcessingChange = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//数据源变化监听器（观察者模式），实现了ContentObserver类</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ForceLoadContentObserver</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ContentObserver</span> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">ForceLoadContentObserver</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> Handler()); } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">deliverSelfNotifications</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onChange</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> selfChange) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//实质是调运Loader的forceLoad方法</span> onContentChanged(); } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//Loader加载完成接口，当加载完成时Loader通知loaderManager,loaderManager再回调我们initLoader方法的callback</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">interface</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">OnLoadCompleteListener</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">D</span>> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoadComplete</span>(Loader<D> loader, D data); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//LoaderManager中监听cancel，同上类似</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">interface</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">OnLoadCanceledListener</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">D</span>> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoadCanceled</span>(Loader<D> loader); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//构造方法</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">Loader</span>(Context context) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//mContext持有Application的Context，防止泄露内存等</span> mContext = context.getApplicationContext(); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//加载完成时回调传递加载数据结果，实质是对OnLoadCompleteListener接口方法的封装</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">deliverResult</span>(D data) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mListener != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mListener.onLoadComplete(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>, data); } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//类似同上，对OnLoadCanceledListener的方法的封装</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">deliverCancellation</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mOnLoadCanceledListener != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mOnLoadCanceledListener.onLoadCanceled(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> Context <span class="hljs-title" style="box-sizing: border-box;">getContext</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mContext; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> <span class="hljs-title" style="box-sizing: border-box;">getId</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mId; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">registerListener</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, OnLoadCompleteListener<D> listener) { mListener = listener; mId = id; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">unregisterListener</span>(OnLoadCompleteListener<D> listener) { mListener = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">registerOnLoadCanceledListener</span>(OnLoadCanceledListener<D> listener) { mOnLoadCanceledListener = listener; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">unregisterOnLoadCanceledListener</span>(OnLoadCanceledListener<D> listener) { mOnLoadCanceledListener = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">isStarted</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mStarted; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">isAbandoned</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mAbandoned; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">isReset</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mReset; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//开始加载数据时LoaderManager会调用该方法</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">startLoading</span>() { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//设置标记</span> mStarted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; mReset = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; mAbandoned = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; onStartLoading(); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//真正开始加载数据的地方******空方法，子类实现！！！！！！</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onStartLoading</span>() { } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//取消Loader的方法</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">cancelLoad</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> onCancelLoad(); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//真正取消的地方******，子类实现！！！！！！return false表示取消失败（因为已完成或未开始）</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">onCancelLoad</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//强制重新Loader，放弃旧数据</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">forceLoad</span>() { onForceLoad(); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//真正重新Loader的地方******空方法，子类实现！！！！！！</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onForceLoad</span>() { } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//同上</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">stopLoading</span>() { mStarted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; onStopLoading(); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onStopLoading</span>() { } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//同上</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">abandon</span>() { mAbandoned = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; onAbandon(); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onAbandon</span>() { } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//同上</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">reset</span>() { onReset(); mReset = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; mStarted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; mAbandoned = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; mContentChanged = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; mProcessingChange = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onReset</span>() { } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//Loader数据变化的一些标记处理</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">takeContentChanged</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> res = mContentChanged; mContentChanged = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; mProcessingChange |= res; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> res; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">commitContentChanged</span>() { mProcessingChange = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">rollbackContentChanged</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mProcessingChange) { mContentChanged = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//上面ForceLoadContentObserver内部类的onChange方法调运</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onContentChanged</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mStarted) { forceLoad(); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { mContentChanged = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//一些方便调试的方法</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> String <span class="hljs-title" style="box-sizing: border-box;">dataToString</span>(D data) <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> String <span class="hljs-title" style="box-sizing: border-box;">toString</span>() <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">dump</span>(String prefix, FileDescriptor fd, PrintWriter writer, String[] args)}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li><li style="box-sizing: border-box; padding: 0px 5px;">37</li><li style="box-sizing: border-box; padding: 0px 5px;">38</li><li style="box-sizing: border-box; padding: 0px 5px;">39</li><li style="box-sizing: border-box; padding: 0px 5px;">40</li><li style="box-sizing: border-box; padding: 0px 5px;">41</li><li style="box-sizing: border-box; padding: 0px 5px;">42</li><li style="box-sizing: border-box; padding: 0px 5px;">43</li><li style="box-sizing: border-box; padding: 0px 5px;">44</li><li style="box-sizing: border-box; padding: 0px 5px;">45</li><li style="box-sizing: border-box; padding: 0px 5px;">46</li><li style="box-sizing: border-box; padding: 0px 5px;">47</li><li style="box-sizing: border-box; padding: 0px 5px;">48</li><li style="box-sizing: border-box; padding: 0px 5px;">49</li><li style="box-sizing: border-box; padding: 0px 5px;">50</li><li style="box-sizing: border-box; padding: 0px 5px;">51</li><li style="box-sizing: border-box; padding: 0px 5px;">52</li><li style="box-sizing: border-box; padding: 0px 5px;">53</li><li style="box-sizing: border-box; padding: 0px 5px;">54</li><li style="box-sizing: border-box; padding: 0px 5px;">55</li><li style="box-sizing: border-box; padding: 0px 5px;">56</li><li style="box-sizing: border-box; padding: 0px 5px;">57</li><li style="box-sizing: border-box; padding: 0px 5px;">58</li><li style="box-sizing: border-box; padding: 0px 5px;">59</li><li style="box-sizing: border-box; padding: 0px 5px;">60</li><li style="box-sizing: border-box; padding: 0px 5px;">61</li><li style="box-sizing: border-box; padding: 0px 5px;">62</li><li style="box-sizing: border-box; padding: 0px 5px;">63</li><li style="box-sizing: border-box; padding: 0px 5px;">64</li><li style="box-sizing: border-box; padding: 0px 5px;">65</li><li style="box-sizing: border-box; padding: 0px 5px;">66</li><li style="box-sizing: border-box; padding: 0px 5px;">67</li><li style="box-sizing: border-box; padding: 0px 5px;">68</li><li style="box-sizing: border-box; padding: 0px 5px;">69</li><li style="box-sizing: border-box; padding: 0px 5px;">70</li><li style="box-sizing: border-box; padding: 0px 5px;">71</li><li style="box-sizing: border-box; padding: 0px 5px;">72</li><li style="box-sizing: border-box; padding: 0px 5px;">73</li><li style="box-sizing: border-box; padding: 0px 5px;">74</li><li style="box-sizing: border-box; padding: 0px 5px;">75</li><li style="box-sizing: border-box; padding: 0px 5px;">76</li><li style="box-sizing: border-box; padding: 0px 5px;">77</li><li style="box-sizing: border-box; padding: 0px 5px;">78</li><li style="box-sizing: border-box; padding: 0px 5px;">79</li><li style="box-sizing: border-box; padding: 0px 5px;">80</li><li style="box-sizing: border-box; padding: 0px 5px;">81</li><li style="box-sizing: border-box; padding: 0px 5px;">82</li><li style="box-sizing: border-box; padding: 0px 5px;">83</li><li style="box-sizing: border-box; padding: 0px 5px;">84</li><li style="box-sizing: border-box; padding: 0px 5px;">85</li><li style="box-sizing: border-box; padding: 0px 5px;">86</li><li style="box-sizing: border-box; padding: 0px 5px;">87</li><li style="box-sizing: border-box; padding: 0px 5px;">88</li><li style="box-sizing: border-box; padding: 0px 5px;">89</li><li style="box-sizing: border-box; padding: 0px 5px;">90</li><li style="box-sizing: border-box; padding: 0px 5px;">91</li><li style="box-sizing: border-box; padding: 0px 5px;">92</li><li style="box-sizing: border-box; padding: 0px 5px;">93</li><li style="box-sizing: border-box; padding: 0px 5px;">94</li><li style="box-sizing: border-box; padding: 0px 5px;">95</li><li style="box-sizing: border-box; padding: 0px 5px;">96</li><li style="box-sizing: border-box; padding: 0px 5px;">97</li><li style="box-sizing: border-box; padding: 0px 5px;">98</li><li style="box-sizing: border-box; padding: 0px 5px;">99</li><li style="box-sizing: border-box; padding: 0px 5px;">100</li><li style="box-sizing: border-box; padding: 0px 5px;">101</li><li style="box-sizing: border-box; padding: 0px 5px;">102</li><li style="box-sizing: border-box; padding: 0px 5px;">103</li><li style="box-sizing: border-box; padding: 0px 5px;">104</li><li style="box-sizing: border-box; padding: 0px 5px;">105</li><li style="box-sizing: border-box; padding: 0px 5px;">106</li><li style="box-sizing: border-box; padding: 0px 5px;">107</li><li style="box-sizing: border-box; padding: 0px 5px;">108</li><li style="box-sizing: border-box; padding: 0px 5px;">109</li><li style="box-sizing: border-box; padding: 0px 5px;">110</li><li style="box-sizing: border-box; padding: 0px 5px;">111</li><li style="box-sizing: border-box; padding: 0px 5px;">112</li><li style="box-sizing: border-box; padding: 0px 5px;">113</li><li style="box-sizing: border-box; padding: 0px 5px;">114</li><li style="box-sizing: border-box; padding: 0px 5px;">115</li><li style="box-sizing: border-box; padding: 0px 5px;">116</li><li style="box-sizing: border-box; padding: 0px 5px;">117</li><li style="box-sizing: border-box; padding: 0px 5px;">118</li><li style="box-sizing: border-box; padding: 0px 5px;">119</li><li style="box-sizing: border-box; padding: 0px 5px;">120</li><li style="box-sizing: border-box; padding: 0px 5px;">121</li><li style="box-sizing: border-box; padding: 0px 5px;">122</li><li style="box-sizing: border-box; padding: 0px 5px;">123</li><li style="box-sizing: border-box; padding: 0px 5px;">124</li><li style="box-sizing: border-box; padding: 0px 5px;">125</li><li style="box-sizing: border-box; padding: 0px 5px;">126</li><li style="box-sizing: border-box; padding: 0px 5px;">127</li><li style="box-sizing: border-box; padding: 0px 5px;">128</li><li style="box-sizing: border-box; padding: 0px 5px;">129</li><li style="box-sizing: border-box; padding: 0px 5px;">130</li><li style="box-sizing: border-box; padding: 0px 5px;">131</li><li style="box-sizing: border-box; padding: 0px 5px;">132</li><li style="box-sizing: border-box; padding: 0px 5px;">133</li><li style="box-sizing: border-box; padding: 0px 5px;">134</li><li style="box-sizing: border-box; padding: 0px 5px;">135</li><li style="box-sizing: border-box; padding: 0px 5px;">136</li><li style="box-sizing: border-box; padding: 0px 5px;">137</li><li style="box-sizing: border-box; padding: 0px 5px;">138</li><li style="box-sizing: border-box; padding: 0px 5px;">139</li><li style="box-sizing: border-box; padding: 0px 5px;">140</li><li style="box-sizing: border-box; padding: 0px 5px;">141</li><li style="box-sizing: border-box; padding: 0px 5px;">142</li><li style="box-sizing: border-box; padding: 0px 5px;">143</li><li style="box-sizing: border-box; padding: 0px 5px;">144</li><li style="box-sizing: border-box; padding: 0px 5px;">145</li><li style="box-sizing: border-box; padding: 0px 5px;">146</li><li style="box-sizing: border-box; padding: 0px 5px;">147</li><li style="box-sizing: border-box; padding: 0px 5px;">148</li><li style="box-sizing: border-box; padding: 0px 5px;">149</li><li style="box-sizing: border-box; padding: 0px 5px;">150</li><li style="box-sizing: border-box; padding: 0px 5px;">151</li><li style="box-sizing: border-box; padding: 0px 5px;">152</li><li style="box-sizing: border-box; padding: 0px 5px;">153</li><li style="box-sizing: border-box; padding: 0px 5px;">154</li><li style="box-sizing: border-box; padding: 0px 5px;">155</li><li style="box-sizing: border-box; padding: 0px 5px;">156</li><li style="box-sizing: border-box; padding: 0px 5px;">157</li><li style="box-sizing: border-box; padding: 0px 5px;">158</li><li style="box-sizing: border-box; padding: 0px 5px;">159</li><li style="box-sizing: border-box; padding: 0px 5px;">160</li><li style="box-sizing: border-box; padding: 0px 5px;">161</li><li style="box-sizing: border-box; padding: 0px 5px;">162</li><li style="box-sizing: border-box; padding: 0px 5px;">163</li><li style="box-sizing: border-box; padding: 0px 5px;">164</li><li style="box-sizing: border-box; padding: 0px 5px;">165</li><li style="box-sizing: border-box; padding: 0px 5px;">166</li><li style="box-sizing: border-box; padding: 0px 5px;">167</li><li style="box-sizing: border-box; padding: 0px 5px;">168</li><li style="box-sizing: border-box; padding: 0px 5px;">169</li><li style="box-sizing: border-box; padding: 0px 5px;">170</li><li style="box-sizing: border-box; padding: 0px 5px;">171</li><li style="box-sizing: border-box; padding: 0px 5px;">172</li><li style="box-sizing: border-box; padding: 0px 5px;">173</li><li style="box-sizing: border-box; padding: 0px 5px;">174</li><li style="box-sizing: border-box; padding: 0px 5px;">175</li></ul>通过上面粗略的分析可以发现，Loader基类无非也就是一个方法接口的定义类，组织预留了一些方法供LoaderManager去调运处理，同时需要子类实现其提供的一些onXXX方法，以便LoaderManager调运Loader的方法时可以触发Loader子类的实现逻辑。
3-3-2 AsyncTaskLoader抽象子类源码浅析
上面既然说了Loader类的作用主要是规定接口，同时供LoaderManager管理，那LoaderManager管理的Loader自然需要做一些事情，也就是说我们需要继承Loader实现一些逻辑操作。然而好在系统API已经帮我们实现了一些简单的封装实现，我们这里就先来看下Loader的直接子类AsyncTaskLoader吧，先来看下该抽象子类的方法及内部类粗略图，如下：
代码分析如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">abstract</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">AsyncTaskLoader</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">D</span>> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">Loader</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">D</span>> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> String TAG = <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"AsyncTaskLoader"</span>; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> DEBUG = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//LoadTask内部类是对AsyncTask的封装，实现了Runnable接口</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> class LoadTask extends AsyncTask<Void, Void, D> implements Runnable { ...... <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> D <span class="hljs-title" style="box-sizing: border-box;">doInBackground</span>(Void... params) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">try</span> { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//AsyncTask的子线程中执行AsyncTaskLoader的onLoadInBackground方法！！！！重点</span> D data = AsyncTaskLoader.<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.onLoadInBackground(); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//把执行结果数据D返回到UI线程</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> data; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">catch</span> (OperationCanceledException ex) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!isCancelled()) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> ex; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">/* Runs on the UI thread */</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onPostExecute</span>(D data) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//AsyncTask子线程执行完毕后回调AsyncTaskLoader的dispatchOnLoadComplete方法</span> AsyncTaskLoader.<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.dispatchOnLoadComplete(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>, data); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">/* Runs on the UI thread */</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onCancelled</span>(D data) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//取消AsyncTask时调运</span> AsyncTaskLoader.<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.dispatchOnCancelled(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>, data); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//Runnable的实现方法</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">run</span>() { waiting = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; AsyncTaskLoader.<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.executePendingTask(); } ...... } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> Executor mExecutor; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">volatile</span> LoadTask mTask; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">volatile</span> LoadTask mCancellingTask; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">long</span> mUpdateThrottle; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">long</span> mLastLoadCompleteTime = -<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">10000</span>; Handler mHandler; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//public构造方法</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">AsyncTaskLoader</span>(Context context) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>(context, AsyncTask.THREAD_POOL_EXECUTOR); } <span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** {@hide} 无法被外部调运的构造方法 */</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">AsyncTaskLoader</span>(Context context, Executor executor) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>(context); mExecutor = executor; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">setUpdateThrottle</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">long</span> delayMS) { mUpdateThrottle = delayMS; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (delayMS != <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>) { mHandler = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> Handler(); } } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onForceLoad</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>.onForceLoad(); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//取消当前的Loader</span> cancelLoad(); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//新建task并执行</span> mTask = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> LoadTask(); executePendingTask(); } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">onCancelLoad</span>() { ...... } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onCanceled</span>(D data) { } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//LoadTask的Runnable方法run中执行</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> executePendingTask() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCancellingTask == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> && mTask != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mTask.waiting) { mTask.waiting = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; mHandler.removeCallbacks(mTask); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mUpdateThrottle > <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">long</span> now = SystemClock.uptimeMillis(); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (now < (mLastLoadCompleteTime+mUpdateThrottle)) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Not yet time to do another load.</span> mTask.waiting = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; mHandler.postAtTime(mTask, mLastLoadCompleteTime+mUpdateThrottle); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span>; } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//真正的触发执行AsyncTask方法</span> mTask.executeOnExecutor(mExecutor, (Void[]) <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>); } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> dispatchOnCancelled(LoadTask task, D data) { onCanceled(data); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCancellingTask == task) { rollbackContentChanged(); mLastLoadCompleteTime = SystemClock.uptimeMillis(); mCancellingTask = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//触发Loader的接口方法onLoadCanceled，在LoaderManager中实现</span> deliverCancellation(); executePendingTask(); } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> dispatchOnLoadComplete(LoadTask task, D data) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mTask != task) { dispatchOnCancelled(task, data); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (isAbandoned()) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// This cursor has been abandoned; just cancel the new data.</span> onCanceled(data); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { commitContentChanged(); mLastLoadCompleteTime = SystemClock.uptimeMillis(); mTask = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//触发Loader的接口方法onLoadComplete，在LoaderManager中实现</span> deliverResult(data); } } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//需要子类实现！！！！！在子线程中执行</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">abstract</span> D <span class="hljs-title" style="box-sizing: border-box;">loadInBackground</span>(); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//LoadTask（AsyncTask的子线程中回调）中调运</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> D <span class="hljs-title" style="box-sizing: border-box;">onLoadInBackground</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> loadInBackground(); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//LoadTask（AsyncTask的onCancelLoad中回调）调运</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">cancelLoadInBackground</span>() { } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">isLoadInBackgroundCanceled</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mCancellingTask != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//锁标记处理</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">waitForLoader</span>() { LoadTask task = mTask; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (task != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { task.waitForLoader(); } }}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li><li style="box-sizing: border-box; padding: 0px 5px;">37</li><li style="box-sizing: border-box; padding: 0px 5px;">38</li><li style="box-sizing: border-box; padding: 0px 5px;">39</li><li style="box-sizing: border-box; padding: 0px 5px;">40</li><li style="box-sizing: border-box; padding: 0px 5px;">41</li><li style="box-sizing: border-box; padding: 0px 5px;">42</li><li style="box-sizing: border-box; padding: 0px 5px;">43</li><li style="box-sizing: border-box; padding: 0px 5px;">44</li><li style="box-sizing: border-box; padding: 0px 5px;">45</li><li style="box-sizing: border-box; padding: 0px 5px;">46</li><li style="box-sizing: border-box; padding: 0px 5px;">47</li><li style="box-sizing: border-box; padding: 0px 5px;">48</li><li style="box-sizing: border-box; padding: 0px 5px;">49</li><li style="box-sizing: border-box; padding: 0px 5px;">50</li><li style="box-sizing: border-box; padding: 0px 5px;">51</li><li style="box-sizing: border-box; padding: 0px 5px;">52</li><li style="box-sizing: border-box; padding: 0px 5px;">53</li><li style="box-sizing: border-box; padding: 0px 5px;">54</li><li style="box-sizing: border-box; padding: 0px 5px;">55</li><li style="box-sizing: border-box; padding: 0px 5px;">56</li><li style="box-sizing: border-box; padding: 0px 5px;">57</li><li style="box-sizing: border-box; padding: 0px 5px;">58</li><li style="box-sizing: border-box; padding: 0px 5px;">59</li><li style="box-sizing: border-box; padding: 0px 5px;">60</li><li style="box-sizing: border-box; padding: 0px 5px;">61</li><li style="box-sizing: border-box; padding: 0px 5px;">62</li><li style="box-sizing: border-box; padding: 0px 5px;">63</li><li style="box-sizing: border-box; padding: 0px 5px;">64</li><li style="box-sizing: border-box; padding: 0px 5px;">65</li><li style="box-sizing: border-box; padding: 0px 5px;">66</li><li style="box-sizing: border-box; padding: 0px 5px;">67</li><li style="box-sizing: border-box; padding: 0px 5px;">68</li><li style="box-sizing: border-box; padding: 0px 5px;">69</li><li style="box-sizing: border-box; padding: 0px 5px;">70</li><li style="box-sizing: border-box; padding: 0px 5px;">71</li><li style="box-sizing: border-box; padding: 0px 5px;">72</li><li style="box-sizing: border-box; padding: 0px 5px;">73</li><li style="box-sizing: border-box; padding: 0px 5px;">74</li><li style="box-sizing: border-box; padding: 0px 5px;">75</li><li style="box-sizing: border-box; padding: 0px 5px;">76</li><li style="box-sizing: border-box; padding: 0px 5px;">77</li><li style="box-sizing: border-box; padding: 0px 5px;">78</li><li style="box-sizing: border-box; padding: 0px 5px;">79</li><li style="box-sizing: border-box; padding: 0px 5px;">80</li><li style="box-sizing: border-box; padding: 0px 5px;">81</li><li style="box-sizing: border-box; padding: 0px 5px;">82</li><li style="box-sizing: border-box; padding: 0px 5px;">83</li><li style="box-sizing: border-box; padding: 0px 5px;">84</li><li style="box-sizing: border-box; padding: 0px 5px;">85</li><li style="box-sizing: border-box; padding: 0px 5px;">86</li><li style="box-sizing: border-box; padding: 0px 5px;">87</li><li style="box-sizing: border-box; padding: 0px 5px;">88</li><li style="box-sizing: border-box; padding: 0px 5px;">89</li><li style="box-sizing: border-box; padding: 0px 5px;">90</li><li style="box-sizing: border-box; padding: 0px 5px;">91</li><li style="box-sizing: border-box; padding: 0px 5px;">92</li><li style="box-sizing: border-box; padding: 0px 5px;">93</li><li style="box-sizing: border-box; padding: 0px 5px;">94</li><li style="box-sizing: border-box; padding: 0px 5px;">95</li><li style="box-sizing: border-box; padding: 0px 5px;">96</li><li style="box-sizing: border-box; padding: 0px 5px;">97</li><li style="box-sizing: border-box; padding: 0px 5px;">98</li><li style="box-sizing: border-box; padding: 0px 5px;">99</li><li style="box-sizing: border-box; padding: 0px 5px;">100</li><li style="box-sizing: border-box; padding: 0px 5px;">101</li><li style="box-sizing: border-box; padding: 0px 5px;">102</li><li style="box-sizing: border-box; padding: 0px 5px;">103</li><li style="box-sizing: border-box; padding: 0px 5px;">104</li><li style="box-sizing: border-box; padding: 0px 5px;">105</li><li style="box-sizing: border-box; padding: 0px 5px;">106</li><li style="box-sizing: border-box; padding: 0px 5px;">107</li><li style="box-sizing: border-box; padding: 0px 5px;">108</li><li style="box-sizing: border-box; padding: 0px 5px;">109</li><li style="box-sizing: border-box; padding: 0px 5px;">110</li><li style="box-sizing: border-box; padding: 0px 5px;">111</li><li style="box-sizing: border-box; padding: 0px 5px;">112</li><li style="box-sizing: border-box; padding: 0px 5px;">113</li><li style="box-sizing: border-box; padding: 0px 5px;">114</li><li style="box-sizing: border-box; padding: 0px 5px;">115</li><li style="box-sizing: border-box; padding: 0px 5px;">116</li><li style="box-sizing: border-box; padding: 0px 5px;">117</li><li style="box-sizing: border-box; padding: 0px 5px;">118</li><li style="box-sizing: border-box; padding: 0px 5px;">119</li><li style="box-sizing: border-box; padding: 0px 5px;">120</li><li style="box-sizing: border-box; padding: 0px 5px;">121</li><li style="box-sizing: border-box; padding: 0px 5px;">122</li><li style="box-sizing: border-box; padding: 0px 5px;">123</li><li style="box-sizing: border-box; padding: 0px 5px;">124</li><li style="box-sizing: border-box; padding: 0px 5px;">125</li><li style="box-sizing: border-box; padding: 0px 5px;">126</li><li style="box-sizing: border-box; padding: 0px 5px;">127</li><li style="box-sizing: border-box; padding: 0px 5px;">128</li><li style="box-sizing: border-box; padding: 0px 5px;">129</li><li style="box-sizing: border-box; padding: 0px 5px;">130</li><li style="box-sizing: border-box; padding: 0px 5px;">131</li><li style="box-sizing: border-box; padding: 0px 5px;">132</li><li style="box-sizing: border-box; padding: 0px 5px;">133</li><li style="box-sizing: border-box; padding: 0px 5px;">134</li><li style="box-sizing: border-box; padding: 0px 5px;">135</li><li style="box-sizing: border-box; padding: 0px 5px;">136</li><li style="box-sizing: border-box; padding: 0px 5px;">137</li><li style="box-sizing: border-box; padding: 0px 5px;">138</li><li style="box-sizing: border-box; padding: 0px 5px;">139</li><li style="box-sizing: border-box; padding: 0px 5px;">140</li><li style="box-sizing: border-box; padding: 0px 5px;">141</li><li style="box-sizing: border-box; padding: 0px 5px;">142</li><li style="box-sizing: border-box; padding: 0px 5px;">143</li><li style="box-sizing: border-box; padding: 0px 5px;">144</li><li style="box-sizing: border-box; padding: 0px 5px;">145</li><li style="box-sizing: border-box; padding: 0px 5px;">146</li><li style="box-sizing: border-box; padding: 0px 5px;">147</li><li style="box-sizing: border-box; padding: 0px 5px;">148</li><li style="box-sizing: border-box; padding: 0px 5px;">149</li><li style="box-sizing: border-box; padding: 0px 5px;">150</li><li style="box-sizing: border-box; padding: 0px 5px;">151</li><li style="box-sizing: border-box; padding: 0px 5px;">152</li><li style="box-sizing: border-box; padding: 0px 5px;">153</li><li style="box-sizing: border-box; padding: 0px 5px;">154</li><li style="box-sizing: border-box; padding: 0px 5px;">155</li><li style="box-sizing: border-box; padding: 0px 5px;">156</li><li style="box-sizing: border-box; padding: 0px 5px;">157</li><li style="box-sizing: border-box; padding: 0px 5px;">158</li><li style="box-sizing: border-box; padding: 0px 5px;">159</li><li style="box-sizing: border-box; padding: 0px 5px;">160</li></ul>可以看见上面继承Loader的AsyncTaskLoader其实质是提供了一个基于AsyncTask工作机制的Loader（子类LoadTask继承AsyncTask<Void, Void, D>，并且实现了Runable接口，功能十分强大。），但是不可直接用，因为其为abstract抽象类，所以我们需要继承实现它才可以使用，然而好在系统API已经帮我们提供了他现成的子类CursorLoader，但CursorLoader同时也限制了Loader的泛型数据为Cursor类型。当然了，我们如果想要Loader自己的类型数据那也很简单—继承实现AsyncTaskLoader即可，后面会给出例子的。
3-3-3 CursorLoader子类源码浅析
有了上面继承自Loader的抽象AsyncTaskLoader，接下来我们就来看看SDK为我们提供的抽象AsyncTaskLoader实现类CursorLoader，我们先来粗略看看该类的方法图，如下：
具体代码分析如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//继承自AsyncTaskLoader，数据类型为Cursor的Loader异步加载实现类</span><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">CursorLoader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">AsyncTaskLoader</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">Cursor</span>> {</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//Cursor的子类ForceLoadContentObserver</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> ForceLoadContentObserver mObserver; Uri mUri; String[] mProjection; String mSelection; String[] mSelectionArgs; String mSortOrder; Cursor mCursor; CancellationSignal mCancellationSignal; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">/* Runs on a worker thread 最核心的实现方法，在这里查询获取数据 */</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> Cursor <span class="hljs-title" style="box-sizing: border-box;">loadInBackground</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">synchronized</span> (<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (isLoadInBackgroundCanceled()) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> OperationCanceledException(); } mCancellationSignal = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> CancellationSignal(); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">try</span> { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//不过多解释，耗时的查询操作</span> Cursor cursor = getContext().getContentResolver().query(mUri, mProjection, mSelection, mSelectionArgs, mSortOrder, mCancellationSignal); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (cursor != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">try</span> { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Ensure the cursor window is filled.</span> cursor.getCount(); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//给Cursor设置观察者；ContentProvider通知Cursor的观察者数据发生了改变，Cursor通知CursorLoader的观察者数据发生了改变，CursorLoader通过ContentProvider重新加载新的数据</span> cursor.registerContentObserver(mObserver); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">catch</span> (RuntimeException ex) { cursor.close(); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> ex; } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> cursor; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">finally</span> { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">synchronized</span> (<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>) { mCancellationSignal = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; } } } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">cancelLoadInBackground</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>.cancelLoadInBackground(); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">synchronized</span> (<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCancellationSignal != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mCancellationSignal.cancel(); } } } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">/* Runs on the UI thread */</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">deliverResult</span>(Cursor cursor) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (isReset()) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// An async query came in while the loader is stopped</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (cursor != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { cursor.close(); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span>; } Cursor oldCursor = mCursor; mCursor = cursor; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (isStarted()) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>.deliverResult(cursor); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (oldCursor != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> && oldCursor != cursor && !oldCursor.isClosed()) { oldCursor.close(); } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">CursorLoader</span>(Context context) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>(context); mObserver = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> ForceLoadContentObserver(); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">CursorLoader</span>(Context context, Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>(context); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//新建一个当前类（Loader）的内部类对象，数据库变化时调运ForceLoadContentObserver的onChange方法，onChange调运Loader的onContentChanged方法，onContentChanged调运Loader的forceLoad方法</span> mObserver = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> ForceLoadContentObserver(); mUri = uri; mProjection = projection; mSelection = selection; mSelectionArgs = selectionArgs; mSortOrder = sortOrder; } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onStartLoading</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCursor != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { deliverResult(mCursor); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (takeContentChanged() || mCursor == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { forceLoad(); } } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onStopLoading</span>() { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Attempt to cancel the current load task if possible.</span> cancelLoad(); } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onCanceled</span>(Cursor cursor) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (cursor != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> && !cursor.isClosed()) { cursor.close(); } } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onReset</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>.onReset(); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Ensure the loader is stopped</span> onStopLoading(); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mCursor != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> && !mCursor.isClosed()) { mCursor.close(); } mCursor = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> Uri <span class="hljs-title" style="box-sizing: border-box;">getUri</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mUri; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">setUri</span>(Uri uri) { mUri = uri; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> String[] <span class="hljs-title" style="box-sizing: border-box;">getProjection</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mProjection; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">setProjection</span>(String[] projection) { mProjection = projection; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> String <span class="hljs-title" style="box-sizing: border-box;">getSelection</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mSelection; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">setSelection</span>(String selection) { mSelection = selection; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> String[] <span class="hljs-title" style="box-sizing: border-box;">getSelectionArgs</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mSelectionArgs; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">setSelectionArgs</span>(String[] selectionArgs) { mSelectionArgs = selectionArgs; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> String <span class="hljs-title" style="box-sizing: border-box;">getSortOrder</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mSortOrder; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">setSortOrder</span>(String sortOrder) { mSortOrder = sortOrder; }}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li><li style="box-sizing: border-box; padding: 0px 5px;">37</li><li style="box-sizing: border-box; padding: 0px 5px;">38</li><li style="box-sizing: border-box; padding: 0px 5px;">39</li><li style="box-sizing: border-box; padding: 0px 5px;">40</li><li style="box-sizing: border-box; padding: 0px 5px;">41</li><li style="box-sizing: border-box; padding: 0px 5px;">42</li><li style="box-sizing: border-box; padding: 0px 5px;">43</li><li style="box-sizing: border-box; padding: 0px 5px;">44</li><li style="box-sizing: border-box; padding: 0px 5px;">45</li><li style="box-sizing: border-box; padding: 0px 5px;">46</li><li style="box-sizing: border-box; padding: 0px 5px;">47</li><li style="box-sizing: border-box; padding: 0px 5px;">48</li><li style="box-sizing: border-box; padding: 0px 5px;">49</li><li style="box-sizing: border-box; padding: 0px 5px;">50</li><li style="box-sizing: border-box; padding: 0px 5px;">51</li><li style="box-sizing: border-box; padding: 0px 5px;">52</li><li style="box-sizing: border-box; padding: 0px 5px;">53</li><li style="box-sizing: border-box; padding: 0px 5px;">54</li><li style="box-sizing: border-box; padding: 0px 5px;">55</li><li style="box-sizing: border-box; padding: 0px 5px;">56</li><li style="box-sizing: border-box; padding: 0px 5px;">57</li><li style="box-sizing: border-box; padding: 0px 5px;">58</li><li style="box-sizing: border-box; padding: 0px 5px;">59</li><li style="box-sizing: border-box; padding: 0px 5px;">60</li><li style="box-sizing: border-box; padding: 0px 5px;">61</li><li style="box-sizing: border-box; padding: 0px 5px;">62</li><li style="box-sizing: border-box; padding: 0px 5px;">63</li><li style="box-sizing: border-box; padding: 0px 5px;">64</li><li style="box-sizing: border-box; padding: 0px 5px;">65</li><li style="box-sizing: border-box; padding: 0px 5px;">66</li><li style="box-sizing: border-box; padding: 0px 5px;">67</li><li style="box-sizing: border-box; padding: 0px 5px;">68</li><li style="box-sizing: border-box; padding: 0px 5px;">69</li><li style="box-sizing: border-box; padding: 0px 5px;">70</li><li style="box-sizing: border-box; padding: 0px 5px;">71</li><li style="box-sizing: border-box; padding: 0px 5px;">72</li><li style="box-sizing: border-box; padding: 0px 5px;">73</li><li style="box-sizing: border-box; padding: 0px 5px;">74</li><li style="box-sizing: border-box; padding: 0px 5px;">75</li><li style="box-sizing: border-box; padding: 0px 5px;">76</li><li style="box-sizing: border-box; padding: 0px 5px;">77</li><li style="box-sizing: border-box; padding: 0px 5px;">78</li><li style="box-sizing: border-box; padding: 0px 5px;">79</li><li style="box-sizing: border-box; padding: 0px 5px;">80</li><li style="box-sizing: border-box; padding: 0px 5px;">81</li><li style="box-sizing: border-box; padding: 0px 5px;">82</li><li style="box-sizing: border-box; padding: 0px 5px;">83</li><li style="box-sizing: border-box; padding: 0px 5px;">84</li><li style="box-sizing: border-box; padding: 0px 5px;">85</li><li style="box-sizing: border-box; padding: 0px 5px;">86</li><li style="box-sizing: border-box; padding: 0px 5px;">87</li><li style="box-sizing: border-box; padding: 0px 5px;">88</li><li style="box-sizing: border-box; padding: 0px 5px;">89</li><li style="box-sizing: border-box; padding: 0px 5px;">90</li><li style="box-sizing: border-box; padding: 0px 5px;">91</li><li style="box-sizing: border-box; padding: 0px 5px;">92</li><li style="box-sizing: border-box; padding: 0px 5px;">93</li><li style="box-sizing: border-box; padding: 0px 5px;">94</li><li style="box-sizing: border-box; padding: 0px 5px;">95</li><li style="box-sizing: border-box; padding: 0px 5px;">96</li><li style="box-sizing: border-box; padding: 0px 5px;">97</li><li style="box-sizing: border-box; padding: 0px 5px;">98</li><li style="box-sizing: border-box; padding: 0px 5px;">99</li><li style="box-sizing: border-box; padding: 0px 5px;">100</li><li style="box-sizing: border-box; padding: 0px 5px;">101</li><li style="box-sizing: border-box; padding: 0px 5px;">102</li><li style="box-sizing: border-box; padding: 0px 5px;">103</li><li style="box-sizing: border-box; padding: 0px 5px;">104</li><li style="box-sizing: border-box; padding: 0px 5px;">105</li><li style="box-sizing: border-box; padding: 0px 5px;">106</li><li style="box-sizing: border-box; padding: 0px 5px;">107</li><li style="box-sizing: border-box; padding: 0px 5px;">108</li><li style="box-sizing: border-box; padding: 0px 5px;">109</li><li style="box-sizing: border-box; padding: 0px 5px;">110</li><li style="box-sizing: border-box; padding: 0px 5px;">111</li><li style="box-sizing: border-box; padding: 0px 5px;">112</li><li style="box-sizing: border-box; padding: 0px 5px;">113</li><li style="box-sizing: border-box; padding: 0px 5px;">114</li><li style="box-sizing: border-box; padding: 0px 5px;">115</li><li style="box-sizing: border-box; padding: 0px 5px;">116</li><li style="box-sizing: border-box; padding: 0px 5px;">117</li><li style="box-sizing: border-box; padding: 0px 5px;">118</li><li style="box-sizing: border-box; padding: 0px 5px;">119</li><li style="box-sizing: border-box; padding: 0px 5px;">120</li><li style="box-sizing: border-box; padding: 0px 5px;">121</li><li style="box-sizing: border-box; padding: 0px 5px;">122</li><li style="box-sizing: border-box; padding: 0px 5px;">123</li><li style="box-sizing: border-box; padding: 0px 5px;">124</li><li style="box-sizing: border-box; padding: 0px 5px;">125</li><li style="box-sizing: border-box; padding: 0px 5px;">126</li><li style="box-sizing: border-box; padding: 0px 5px;">127</li><li style="box-sizing: border-box; padding: 0px 5px;">128</li><li style="box-sizing: border-box; padding: 0px 5px;">129</li><li style="box-sizing: border-box; padding: 0px 5px;">130</li><li style="box-sizing: border-box; padding: 0px 5px;">131</li><li style="box-sizing: border-box; padding: 0px 5px;">132</li><li style="box-sizing: border-box; padding: 0px 5px;">133</li><li style="box-sizing: border-box; padding: 0px 5px;">134</li><li style="box-sizing: border-box; padding: 0px 5px;">135</li><li style="box-sizing: border-box; padding: 0px 5px;">136</li><li style="box-sizing: border-box; padding: 0px 5px;">137</li><li style="box-sizing: border-box; padding: 0px 5px;">138</li><li style="box-sizing: border-box; padding: 0px 5px;">139</li><li style="box-sizing: border-box; padding: 0px 5px;">140</li><li style="box-sizing: border-box; padding: 0px 5px;">141</li><li style="box-sizing: border-box; padding: 0px 5px;">142</li><li style="box-sizing: border-box; padding: 0px 5px;">143</li><li style="box-sizing: border-box; padding: 0px 5px;">144</li><li style="box-sizing: border-box; padding: 0px 5px;">145</li><li style="box-sizing: border-box; padding: 0px 5px;">146</li><li style="box-sizing: border-box; padding: 0px 5px;">147</li><li style="box-sizing: border-box; padding: 0px 5px;">148</li><li style="box-sizing: border-box; padding: 0px 5px;">149</li><li style="box-sizing: border-box; padding: 0px 5px;">150</li><li style="box-sizing: border-box; padding: 0px 5px;">151</li><li style="box-sizing: border-box; padding: 0px 5px;">152</li><li style="box-sizing: border-box; padding: 0px 5px;">153</li><li style="box-sizing: border-box; padding: 0px 5px;">154</li><li style="box-sizing: border-box; padding: 0px 5px;">155</li><li style="box-sizing: border-box; padding: 0px 5px;">156</li><li style="box-sizing: border-box; padding: 0px 5px;">157</li><li style="box-sizing: border-box; padding: 0px 5px;">158</li><li style="box-sizing: border-box; padding: 0px 5px;">159</li><li style="box-sizing: border-box; padding: 0px 5px;">160</li><li style="box-sizing: border-box; padding: 0px 5px;">161</li><li style="box-sizing: border-box; padding: 0px 5px;">162</li><li style="box-sizing: border-box; padding: 0px 5px;">163</li><li style="box-sizing: border-box; padding: 0px 5px;">164</li><li style="box-sizing: border-box; padding: 0px 5px;">165</li><li style="box-sizing: border-box; padding: 0px 5px;">166</li><li style="box-sizing: border-box; padding: 0px 5px;">167</li><li style="box-sizing: border-box; padding: 0px 5px;">168</li><li style="box-sizing: border-box; padding: 0px 5px;">169</li><li style="box-sizing: border-box; padding: 0px 5px;">170</li><li style="box-sizing: border-box; padding: 0px 5px;">171</li><li style="box-sizing: border-box; padding: 0px 5px;">172</li><li style="box-sizing: border-box; padding: 0px 5px;">173</li></ul>可以发现，CursorLoader的封装大大简化了应用开发者代码的复杂度；它完全就是一个异步的数据库查询瑞士军刀，没有啥特别需要分析的地方，所以不再过多说明。
3-4 Loaders相关源码浅析总结
通过上面我们的源码分析和分析前那副图可以总结如下结论：
一次完整的数据加载流程为Activity调用LoaderManager的doStart()方法，然后LoaderManager调用Loader的startLoading()方法，然后Loader调运AsyncTaskLoader的doingBackground()方法进行耗时数据加载，然后AsyncTaskLoader回调LoaderManager的complete数据加载完成方法，接着LoaderManager回调我们在Activity中实现的callback中的onLoadFinish()方法。
Acivity和Fragment的生命周期主动管理了LoaderManager，每个Activity用一个ArrayMap的mAllLoaderManager来保存当前Activity及其附属Frament的唯一LoaderManager；在Activity配置发生变化时，Activity在destory前会保存mAllLoaderManager，当Activity再重新创建时，会在Activity的onAttcach()、onCreate()、performStart()方法中恢复mAllLoaderManager。
LoaderManager给Activity提供了管理自己的一些方法；同时主动管理了对应的Loader，它把每一个Loader封装为LoadInfo对象，同时它负责主动调运管理Loader的startLoading()、stopLoading()、,forceLoad()等方法。
由于整个Activity和Fragment主动管理了Loader，所以关于Loader的释放（譬如CursorLoader的Cursor关闭等）不需要我们人为处理，Loader框架会帮我们很好的处理的；同时特别注意，对于CursorLoader，当我们数据源发生变化时Loader框架会通过ContentObserver调用onContentChanged的forceLoad方法重新请求数据进行回调刷新。
好了，至此你会发现Loader真的很牛叉，No！应该是Google的工程师真的很牛叉，架构真的很赞，值得推荐。
【工匠若水 http://blog.csdn.net/yanbober 转载请注明出处。点我开始Android技术交流】
4 应用层开发之Loader进阶实战
上面对于Loader的基础使用及源码框架都进行了简单分析，有了上面的铺垫我们再回过头来看看我们开发中的一些高级技巧，通过这些高级技巧不仅是对前面源码分析的实例验证，也是对自己知识的积累。
4-1 ContentPorvider情况下的CurSorLoader自动刷新
在我们使用CurSorLoader时大家都会考虑一种情况的处理—–当数据库发生变化时如何自动刷新当前UI。呵呵，我们先来说说这个原理，数据库在数据改变时通过ContentPorvider和ContentResolver发出通知，接着ContentProvider通知Cursor的观察者数据发生了变化，然后Cursor通知CursorLoader的观察者数据发生了变化，接着CursorLoader通过ContentProvider加载新数据，完事调用CursorAdapter的changeCursor()用新数据替换旧数据显示。
这个过程具体的实现步骤如下：
对获取的Cursor数据设置需要监听的URI（即，在ContentProvider的query()方法或者Loader的loadingBackground()方法中调用Cursor的setNotificationUri()方法）；
在ContentProvider的insert()、update()、delete()等方法中调用ContentResolver的notifyChange()方法；
通过上面两步我们就能享受CurSorLoader的自动数据刷新功能了；可以发现，所谓的CurSorLoader自动刷新无非就是观察者模式的框架而已，所以不再过多说明。
特别注意：
有些人觉得为了方便可能会将上面第一步对于Cursor设置监听直接写在了ContentProvider的query()方法中，如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> Cursor <span class="hljs-title" style="box-sizing: border-box;">query</span>(Uri uri, String[] projection, String selection, String[] selectionArgs,String sortOrder) { SQLiteDatabase database = sqLiteOpenHelper.getReadableDatabase(); Cursor cursor = database.query(EmailContent.CONTACT_TABLE, projection, selection,selectionArgs, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, sortOrder); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//设置NotificationUri监听</span> cursor.setNotificationUri(contentResolver, EmailContent.MESSAGE); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> cursor;}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li></ul>这里要提醒的是，这种写法在某些场合下是不值得推荐的（譬如大规模上千次并发平凡的调运query操作场合），因为效率极低，他会频繁的通过Binder进行通信，导致system_server不停的调运GC操作，以至于会使系统卡顿。
PS：因为我以前跳过一次这个坑，平时使用应用没啥问题，但是当进行压力测试时却发现LogCat一直在不停的打印GC，同时导致当前系统卡顿，杀掉应用后系统就不卡了，所以基本怀疑问题就出在了应用中，于是通过很多办法去查找（譬如dempsys content去查看个数），最终发现罪魁祸首是这个监听频繁调运导致的，随将其挪到loadingBackground中不再卡顿。
4-2 不使用ContentPorvider且自定义Loader的情况下自动刷新
我们目前的项目其实都使用了ContentPorvider实现，所以就是上面讲的那些情况。但是你一定会问，如果我们应用的数据不用于应用间共享，使用ContentProvider那得多麻烦啊？我先告诉你，是很麻烦，但是Android提供的CursorLoader的API必须使用ContentProvider才能实现数据加载和自动刷新。
这时候你指定会说，那还说个屁！哎，别急，你看看下面这段代码是否会有所感触呢，如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> NoProviderLoader extends AsyncTaskLoader { ...... ForceLoadContentObserver mObserver = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> ForceLoadContentObserver(); ...... <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> Cursor <span class="hljs-title" style="box-sizing: border-box;">loadInBackground</span>() { SQLiteDatabase database = sqLiteOpenHelper.getReadableDatabase(); Cursor cursor = database.query(table, columns, selection, selectionArgs, groupBy, having, orderBy); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (cursor != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//最重要的两行代码！！！！！！</span> cursor.registerContentObserver(mObserver);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//给Cursor设置观察者</span> cursor.setNotificationUri(getContext().getContentResolver(), otificationUri);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//给Cursor设置要观察的URI</span> } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> cursor; } ......}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li></ul>咦？是不是上面代码很奇怪，异步操作的方法中没有使用ContentProvider，而是直接读取了数据库。握草！这不就是我们刚刚想要的需求么，它没有使用ContentProvider提供Cursor数据，同时实现了数据变化自动更新功能。
简单解释下上面代码的原理吧，我们自定义的NoProviderLoader中定义的ForceLoadContentObserver是Loader的一个内部类，上面源码分析已经解释过了，当数据变化时会调运该类的onChange()方法，实质是调运了Loader的forceLoad()方法，所以能够自动刷新，不多解释了。
4-3 Loader自定义之AsyncTaskLoader衍生
可能看到这里你更加会举一反三的反驳一句了，上面搞了半天都是和数据库Cursor相关的东东，难道Loader就不能异步处理别的数据结构么？答案是能，因为你可能已经注意到了Loader和AsyncTaskLoader都是泛型类；既然这样，那我们找猫画虎一把呗，仿照CursorLoader自定义一个自己的异步加载试试，具体实现如下（哈哈，想了又想，这里还是直接给出官方的自定义AsyncTaskLoader好点，毕竟权威些，详细点我查看官方自定义实现Demo）：
官方对于查询已安装App列表的Loader实现，支持新App安装后自动刷新的功能，实现如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * This class holds the per-item data in our Loader. */</span><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">AppEntry</span> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">AppEntry</span>(AppListLoader loader, ApplicationInfo info) { mLoader = loader; mInfo = info; mApkFile = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> File(info.sourceDir); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> ApplicationInfo <span class="hljs-title" style="box-sizing: border-box;">getApplicationInfo</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mInfo; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> String <span class="hljs-title" style="box-sizing: border-box;">getLabel</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mLabel; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> Drawable <span class="hljs-title" style="box-sizing: border-box;">getIcon</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mIcon == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mApkFile.exists()) { mIcon = mInfo.loadIcon(mLoader.mPm); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mIcon; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { mMounted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!mMounted) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// If the app wasn't mounted but is now mounted, reload</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// its icon.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mApkFile.exists()) { mMounted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; mIcon = mInfo.loadIcon(mLoader.mPm); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mIcon; } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mIcon; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mLoader.getContext().getResources().getDrawable( android.R.drawable.sym_def_app_icon); } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> String <span class="hljs-title" style="box-sizing: border-box;">toString</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> mLabel; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> loadLabel(Context context) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mLabel == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> || !mMounted) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!mApkFile.exists()) { mMounted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; mLabel = mInfo.packageName; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { mMounted = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; CharSequence label = mInfo.loadLabel(context.getPackageManager()); mLabel = label != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> ? label.toString() : mInfo.packageName; } } } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> AppListLoader mLoader; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> ApplicationInfo mInfo; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> File mApkFile; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> String mLabel; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> Drawable mIcon; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> mMounted;}<span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * Perform alphabetical comparison of application entry objects. */</span><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> Comparator<AppEntry> ALPHA_COMPARATOR = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> Comparator<AppEntry>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> Collator sCollator = Collator.getInstance(); <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> <span class="hljs-title" style="box-sizing: border-box;">compare</span>(AppEntry object1, AppEntry object2) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> sCollator.compare(object1.getLabel(), object2.getLabel()); }};<span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * Helper for determining if the configuration has changed in an interesting * way so we need to rebuild the app list. */</span><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">InterestingConfigChanges</span> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> Configuration mLastConfiguration = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> Configuration(); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> mLastDensity; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> applyNewConfig(Resources res) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> configChanges = mLastConfiguration.updateFrom(res.getConfiguration()); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> densityChanged = mLastDensity != res.getDisplayMetrics().densityDpi; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (densityChanged || (configChanges&(ActivityInfo.CONFIG_LOCALE |ActivityInfo.CONFIG_UI_MODE|ActivityInfo.CONFIG_SCREEN_LAYOUT)) != <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>) { mLastDensity = res.getDisplayMetrics().densityDpi; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>; }}<span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * Helper class to look for interesting changes to the installed apps * so that the loader can be updated. */</span><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">PackageIntentReceiver</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">BroadcastReceiver</span> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> AppListLoader mLoader; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">PackageIntentReceiver</span>(AppListLoader loader) { mLoader = loader; IntentFilter filter = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> IntentFilter(Intent.ACTION_PACKAGE_ADDED); filter.addAction(Intent.ACTION_PACKAGE_REMOVED); filter.addAction(Intent.ACTION_PACKAGE_CHANGED); filter.addDataScheme(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"package"</span>); mLoader.getContext().registerReceiver(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>, filter); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Register for events related to sdcard installation.</span> IntentFilter sdFilter = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> IntentFilter(); sdFilter.addAction(Intent.ACTION_EXTERNAL_APPLICATIONS_AVAILABLE); sdFilter.addAction(Intent.ACTION_EXTERNAL_APPLICATIONS_UNAVAILABLE); mLoader.getContext().registerReceiver(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>, sdFilter); } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onReceive</span>(Context context, Intent intent) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Tell the loader about the change.</span> mLoader.onContentChanged(); }}<span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * A custom Loader that loads all of the installed applications. */</span><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">AppListLoader</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">AsyncTaskLoader</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">List</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">AppEntry</span>>> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> InterestingConfigChanges mLastConfig = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> InterestingConfigChanges(); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> PackageManager mPm; List<AppEntry> mApps; PackageIntentReceiver mPackageObserver; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">AppListLoader</span>(Context context) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>(context); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Retrieve the package manager for later use; note we don't</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// use 'context' directly but instead the save global application</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// context returned by getContext().</span> mPm = getContext().getPackageManager(); } <span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * This is where the bulk of our work is done. This function is * called in a background thread and should generate a new set of * data to be published by the loader. */</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> List<AppEntry> <span class="hljs-title" style="box-sizing: border-box;">loadInBackground</span>() { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Retrieve all known applications.</span> List<ApplicationInfo> apps = mPm.getInstalledApplications( PackageManager.GET_UNINSTALLED_PACKAGES | PackageManager.GET_DISABLED_COMPONENTS); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (apps == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { apps = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> ArrayList<ApplicationInfo>(); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> Context context = getContext(); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Create corresponding array of entries and load their labels.</span> List<AppEntry> entries = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> ArrayList<AppEntry>(apps.size()); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">for</span> (<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> i=<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>; i<apps.size(); i++) { AppEntry entry = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> AppEntry(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>, apps.get(i)); entry.loadLabel(context); entries.add(entry); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Sort the list.</span> Collections.sort(entries, ALPHA_COMPARATOR); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Done!</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> entries; } <span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * Called when there is new data to deliver to the client. The * super class will take care of delivering it; the implementation * here just adds a little more logic. */</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">deliverResult</span>(List<AppEntry> apps) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (isReset()) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// An async query came in while the loader is stopped. We</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// don't need the result.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (apps != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { onReleaseResources(apps); } } List<AppEntry> oldApps = mApps; mApps = apps; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (isStarted()) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// If the Loader is currently started, we can immediately</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// deliver its results.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>.deliverResult(apps); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// At this point we can release the resources associated with</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// 'oldApps' if needed; now that the new result is delivered we</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// know that it is no longer in use.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (oldApps != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { onReleaseResources(oldApps); } } <span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * Handles a request to start the Loader. */</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onStartLoading</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mApps != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// If we currently have a result available, deliver it</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// immediately.</span> deliverResult(mApps); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Start watching for changes in the app data.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mPackageObserver == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { mPackageObserver = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> PackageIntentReceiver(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Has something interesting in the configuration changed since we</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// last built the app list?</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> configChange = mLastConfig.applyNewConfig(getContext().getResources()); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (takeContentChanged() || mApps == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span> || configChange) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// If the data has changed since the last time it was loaded</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// or is not currently available, start a load.</span> forceLoad(); } } <span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * Handles a request to stop the Loader. */</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onStopLoading</span>() { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Attempt to cancel the current load task if possible.</span> cancelLoad(); } <span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * Handles a request to cancel a load. */</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onCanceled</span>(List<AppEntry> apps) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>.onCanceled(apps); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// At this point we can release the resources associated with 'apps'</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// if needed.</span> onReleaseResources(apps); } <span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * Handles a request to completely reset the Loader. */</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onReset</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>.onReset(); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Ensure the loader is stopped</span> onStopLoading(); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// At this point we can release the resources associated with 'apps'</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// if needed.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mApps != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { onReleaseResources(mApps); mApps = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Stop monitoring for changes.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (mPackageObserver != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { getContext().unregisterReceiver(mPackageObserver); mPackageObserver = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; } } <span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * Helper function to take care of releasing resources associated * with an actively loaded data set. */</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onReleaseResources</span>(List<AppEntry> apps) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// For a simple List<> there is nothing to do. For something</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// like a Cursor, we would close it here.</span> }}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; 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padding: 0px 5px;">78</li><li style="box-sizing: border-box; padding: 0px 5px;">79</li><li style="box-sizing: border-box; padding: 0px 5px;">80</li><li style="box-sizing: border-box; padding: 0px 5px;">81</li><li style="box-sizing: border-box; padding: 0px 5px;">82</li><li style="box-sizing: border-box; padding: 0px 5px;">83</li><li style="box-sizing: border-box; padding: 0px 5px;">84</li><li style="box-sizing: border-box; padding: 0px 5px;">85</li><li style="box-sizing: border-box; padding: 0px 5px;">86</li><li style="box-sizing: border-box; padding: 0px 5px;">87</li><li style="box-sizing: border-box; padding: 0px 5px;">88</li><li style="box-sizing: border-box; padding: 0px 5px;">89</li><li style="box-sizing: border-box; padding: 0px 5px;">90</li><li style="box-sizing: border-box; padding: 0px 5px;">91</li><li style="box-sizing: border-box; padding: 0px 5px;">92</li><li style="box-sizing: border-box; padding: 0px 5px;">93</li><li style="box-sizing: border-box; padding: 0px 5px;">94</li><li style="box-sizing: border-box; padding: 0px 5px;">95</li><li style="box-sizing: border-box; padding: 0px 5px;">96</li><li style="box-sizing: border-box; padding: 0px 5px;">97</li><li style="box-sizing: border-box; padding: 0px 5px;">98</li><li style="box-sizing: border-box; padding: 0px 5px;">99</li><li style="box-sizing: border-box; padding: 0px 5px;">100</li><li style="box-sizing: border-box; padding: 0px 5px;">101</li><li style="box-sizing: border-box; padding: 0px 5px;">102</li><li style="box-sizing: border-box; padding: 0px 5px;">103</li><li style="box-sizing: border-box; padding: 0px 5px;">104</li><li style="box-sizing: border-box; padding: 0px 5px;">105</li><li style="box-sizing: border-box; padding: 0px 5px;">106</li><li style="box-sizing: border-box; padding: 0px 5px;">107</li><li style="box-sizing: border-box; padding: 0px 5px;">108</li><li style="box-sizing: border-box; padding: 0px 5px;">109</li><li style="box-sizing: border-box; padding: 0px 5px;">110</li><li style="box-sizing: border-box; padding: 0px 5px;">111</li><li style="box-sizing: border-box; padding: 0px 5px;">112</li><li style="box-sizing: border-box; padding: 0px 5px;">113</li><li style="box-sizing: border-box; padding: 0px 5px;">114</li><li style="box-sizing: border-box; padding: 0px 5px;">115</li><li style="box-sizing: border-box; padding: 0px 5px;">116</li><li style="box-sizing: border-box; padding: 0px 5px;">117</li><li style="box-sizing: border-box; padding: 0px 5px;">118</li><li style="box-sizing: border-box; padding: 0px 5px;">119</li><li style="box-sizing: border-box; padding: 0px 5px;">120</li><li style="box-sizing: border-box; padding: 0px 5px;">121</li><li style="box-sizing: border-box; padding: 0px 5px;">122</li><li style="box-sizing: border-box; padding: 0px 5px;">123</li><li style="box-sizing: border-box; padding: 0px 5px;">124</li><li style="box-sizing: border-box; padding: 0px 5px;">125</li><li style="box-sizing: border-box; padding: 0px 5px;">126</li><li style="box-sizing: border-box; padding: 0px 5px;">127</li><li style="box-sizing: border-box; padding: 0px 5px;">128</li><li style="box-sizing: border-box; padding: 0px 5px;">129</li><li style="box-sizing: border-box; padding: 0px 5px;">130</li><li style="box-sizing: border-box; padding: 0px 5px;">131</li><li style="box-sizing: border-box; padding: 0px 5px;">132</li><li style="box-sizing: border-box; padding: 0px 5px;">133</li><li style="box-sizing: border-box; padding: 0px 5px;">134</li><li style="box-sizing: border-box; padding: 0px 5px;">135</li><li style="box-sizing: border-box; padding: 0px 5px;">136</li><li style="box-sizing: border-box; padding: 0px 5px;">137</li><li style="box-sizing: border-box; padding: 0px 5px;">138</li><li style="box-sizing: border-box; padding: 0px 5px;">139</li><li style="box-sizing: border-box; padding: 0px 5px;">140</li><li style="box-sizing: border-box; padding: 0px 5px;">141</li><li style="box-sizing: border-box; padding: 0px 5px;">142</li><li style="box-sizing: border-box; padding: 0px 5px;">143</li><li style="box-sizing: border-box; padding: 0px 5px;">144</li><li style="box-sizing: border-box; padding: 0px 5px;">145</li><li style="box-sizing: border-box; padding: 0px 5px;">146</li><li style="box-sizing: border-box; padding: 0px 5px;">147</li><li style="box-sizing: border-box; padding: 0px 5px;">148</li><li style="box-sizing: border-box; padding: 0px 5px;">149</li><li style="box-sizing: border-box; padding: 0px 5px;">150</li><li style="box-sizing: border-box; padding: 0px 5px;">151</li><li style="box-sizing: border-box; padding: 0px 5px;">152</li><li style="box-sizing: border-box; padding: 0px 5px;">153</li><li style="box-sizing: border-box; padding: 0px 5px;">154</li><li style="box-sizing: border-box; padding: 0px 5px;">155</li><li style="box-sizing: border-box; padding: 0px 5px;">156</li><li style="box-sizing: border-box; padding: 0px 5px;">157</li><li style="box-sizing: border-box; padding: 0px 5px;">158</li><li style="box-sizing: border-box; padding: 0px 5px;">159</li><li style="box-sizing: border-box; padding: 0px 5px;">160</li><li style="box-sizing: border-box; padding: 0px 5px;">161</li><li style="box-sizing: border-box; padding: 0px 5px;">162</li><li style="box-sizing: border-box; padding: 0px 5px;">163</li><li style="box-sizing: border-box; padding: 0px 5px;">164</li><li style="box-sizing: border-box; padding: 0px 5px;">165</li><li style="box-sizing: border-box; padding: 0px 5px;">166</li><li style="box-sizing: border-box; padding: 0px 5px;">167</li><li style="box-sizing: border-box; padding: 0px 5px;">168</li><li style="box-sizing: border-box; padding: 0px 5px;">169</li><li style="box-sizing: border-box; padding: 0px 5px;">170</li><li style="box-sizing: border-box; padding: 0px 5px;">171</li><li style="box-sizing: border-box; padding: 0px 5px;">172</li><li style="box-sizing: border-box; padding: 0px 5px;">173</li><li style="box-sizing: border-box; padding: 0px 5px;">174</li><li style="box-sizing: border-box; padding: 0px 5px;">175</li><li style="box-sizing: border-box; padding: 0px 5px;">176</li><li style="box-sizing: border-box; padding: 0px 5px;">177</li><li style="box-sizing: border-box; padding: 0px 5px;">178</li><li style="box-sizing: border-box; padding: 0px 5px;">179</li><li style="box-sizing: border-box; padding: 0px 5px;">180</li><li style="box-sizing: border-box; padding: 0px 5px;">181</li><li style="box-sizing: border-box; padding: 0px 5px;">182</li><li style="box-sizing: border-box; padding: 0px 5px;">183</li><li style="box-sizing: border-box; padding: 0px 5px;">184</li><li style="box-sizing: border-box; padding: 0px 5px;">185</li><li style="box-sizing: border-box; padding: 0px 5px;">186</li><li style="box-sizing: border-box; padding: 0px 5px;">187</li><li style="box-sizing: border-box; padding: 0px 5px;">188</li><li style="box-sizing: border-box; padding: 0px 5px;">189</li><li style="box-sizing: border-box; padding: 0px 5px;">190</li><li style="box-sizing: border-box; padding: 0px 5px;">191</li><li style="box-sizing: border-box; padding: 0px 5px;">192</li><li style="box-sizing: border-box; padding: 0px 5px;">193</li><li style="box-sizing: border-box; padding: 0px 5px;">194</li><li style="box-sizing: border-box; padding: 0px 5px;">195</li><li style="box-sizing: border-box; padding: 0px 5px;">196</li><li style="box-sizing: border-box; padding: 0px 5px;">197</li><li style="box-sizing: border-box; padding: 0px 5px;">198</li><li style="box-sizing: border-box; padding: 0px 5px;">199</li><li style="box-sizing: border-box; padding: 0px 5px;">200</li><li style="box-sizing: border-box; padding: 0px 5px;">201</li><li style="box-sizing: border-box; padding: 0px 5px;">202</li><li style="box-sizing: border-box; padding: 0px 5px;">203</li><li style="box-sizing: border-box; padding: 0px 5px;">204</li><li style="box-sizing: border-box; padding: 0px 5px;">205</li><li style="box-sizing: border-box; padding: 0px 5px;">206</li><li style="box-sizing: border-box; padding: 0px 5px;">207</li><li style="box-sizing: border-box; padding: 0px 5px;">208</li><li style="box-sizing: border-box; padding: 0px 5px;">209</li><li style="box-sizing: border-box; padding: 0px 5px;">210</li><li style="box-sizing: border-box; padding: 0px 5px;">211</li><li style="box-sizing: border-box; padding: 0px 5px;">212</li><li style="box-sizing: border-box; padding: 0px 5px;">213</li><li style="box-sizing: border-box; padding: 0px 5px;">214</li><li style="box-sizing: border-box; padding: 0px 5px;">215</li><li style="box-sizing: border-box; padding: 0px 5px;">216</li><li style="box-sizing: border-box; padding: 0px 5px;">217</li><li style="box-sizing: border-box; padding: 0px 5px;">218</li><li style="box-sizing: border-box; padding: 0px 5px;">219</li><li style="box-sizing: border-box; padding: 0px 5px;">220</li><li style="box-sizing: border-box; padding: 0px 5px;">221</li><li style="box-sizing: border-box; padding: 0px 5px;">222</li><li style="box-sizing: border-box; padding: 0px 5px;">223</li><li style="box-sizing: border-box; padding: 0px 5px;">224</li><li style="box-sizing: border-box; padding: 0px 5px;">225</li><li style="box-sizing: border-box; padding: 0px 5px;">226</li><li style="box-sizing: border-box; padding: 0px 5px;">227</li><li style="box-sizing: border-box; padding: 0px 5px;">228</li><li style="box-sizing: border-box; padding: 0px 5px;">229</li><li style="box-sizing: border-box; padding: 0px 5px;">230</li><li style="box-sizing: border-box; padding: 0px 5px;">231</li><li style="box-sizing: border-box; padding: 0px 5px;">232</li><li style="box-sizing: border-box; padding: 0px 5px;">233</li><li style="box-sizing: border-box; padding: 0px 5px;">234</li><li style="box-sizing: border-box; padding: 0px 5px;">235</li><li style="box-sizing: border-box; padding: 0px 5px;">236</li><li style="box-sizing: border-box; padding: 0px 5px;">237</li><li style="box-sizing: border-box; padding: 0px 5px;">238</li><li style="box-sizing: border-box; padding: 0px 5px;">239</li><li style="box-sizing: border-box; padding: 0px 5px;">240</li><li style="box-sizing: border-box; padding: 0px 5px;">241</li><li style="box-sizing: border-box; padding: 0px 5px;">242</li><li style="box-sizing: border-box; padding: 0px 5px;">243</li><li style="box-sizing: border-box; padding: 0px 5px;">244</li><li style="box-sizing: border-box; padding: 0px 5px;">245</li><li style="box-sizing: border-box; padding: 0px 5px;">246</li><li style="box-sizing: border-box; padding: 0px 5px;">247</li><li style="box-sizing: border-box; padding: 0px 5px;">248</li><li style="box-sizing: border-box; padding: 0px 5px;">249</li><li style="box-sizing: border-box; padding: 0px 5px;">250</li><li style="box-sizing: border-box; padding: 0px 5px;">251</li><li style="box-sizing: border-box; padding: 0px 5px;">252</li><li style="box-sizing: border-box; padding: 0px 5px;">253</li><li style="box-sizing: border-box; padding: 0px 5px;">254</li><li style="box-sizing: border-box; padding: 0px 5px;">255</li><li style="box-sizing: border-box; padding: 0px 5px;">256</li><li style="box-sizing: border-box; padding: 0px 5px;">257</li><li style="box-sizing: border-box; padding: 0px 5px;">258</li><li style="box-sizing: border-box; padding: 0px 5px;">259</li><li style="box-sizing: border-box; padding: 0px 5px;">260</li><li style="box-sizing: border-box; padding: 0px 5px;">261</li><li style="box-sizing: border-box; padding: 0px 5px;">262</li><li style="box-sizing: border-box; padding: 0px 5px;">263</li><li style="box-sizing: border-box; padding: 0px 5px;">264</li><li style="box-sizing: border-box; padding: 0px 5px;">265</li><li style="box-sizing: border-box; padding: 0px 5px;">266</li><li style="box-sizing: border-box; padding: 0px 5px;">267</li><li style="box-sizing: border-box; padding: 0px 5px;">268</li><li style="box-sizing: border-box; padding: 0px 5px;">269</li><li style="box-sizing: border-box; padding: 0px 5px;">270</li><li style="box-sizing: border-box; padding: 0px 5px;">271</li><li style="box-sizing: border-box; padding: 0px 5px;">272</li><li style="box-sizing: border-box; padding: 0px 5px;">273</li><li style="box-sizing: border-box; padding: 0px 5px;">274</li><li style="box-sizing: border-box; padding: 0px 5px;">275</li><li style="box-sizing: border-box; padding: 0px 5px;">276</li><li style="box-sizing: border-box; padding: 0px 5px;">277</li><li style="box-sizing: border-box; padding: 0px 5px;">278</li><li style="box-sizing: border-box; padding: 0px 5px;">279</li><li style="box-sizing: border-box; padding: 0px 5px;">280</li><li style="box-sizing: border-box; padding: 0px 5px;">281</li><li style="box-sizing: border-box; padding: 0px 5px;">282</li></ul>不用多说，上面Loader为Google出品，强大的不得了，我们完全可以仿写这个例子实现自己的请求。
如下为官方对该自定义Loader调运的Demo代码：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">AppListAdapter</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ArrayAdapter</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">AppEntry</span>> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> LayoutInflater mInflater; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">AppListAdapter</span>(Context context) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>(context, android.R.layout.simple_list_item_2); mInflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">setData</span>(List<AppEntry> data) { clear(); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (data != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { addAll(data); } } <span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/** * Populate new items in the list. */</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> View <span class="hljs-title" style="box-sizing: border-box;">getView</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> position, View convertView, ViewGroup parent) { View view; <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (convertView == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) { view = mInflater.inflate(R.layout.list_item_icon_text, parent, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { view = convertView; } AppEntry item = getItem(position); ((ImageView)view.findViewById(R.id.icon)).setImageDrawable(item.getIcon()); ((TextView)view.findViewById(R.id.text)).setText(item.getLabel()); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> view; }}<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">AppListFragment</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ListFragment</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">implements</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">OnQueryTextListener</span>, <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">OnCloseListener</span>, <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">LoaderManager</span>.<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">LoaderCallbacks</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">List</span><<span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">AppEntry</span>>> {</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// This is the Adapter being used to display the list's data.</span> AppListAdapter mAdapter; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// The SearchView for doing filtering.</span> SearchView mSearchView; <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// If non-null, this is the current filter the user has provided.</span> String mCurFilter; <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onActivityCreated</span>(Bundle savedInstanceState) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>.onActivityCreated(savedInstanceState); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Give some text to display if there is no data. In a real</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// application this would come from a resource.</span> setEmptyText(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"No applications"</span>); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// We have a menu item to show in action bar.</span> setHasOptionsMenu(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Create an empty adapter we will use to display the loaded data.</span> mAdapter = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> AppListAdapter(getActivity()); setListAdapter(mAdapter); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Start out with a progress indicator.</span> setListShown(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Prepare the loader. Either re-connect with an existing one,</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// or start a new one.</span> getLoaderManager().initLoader(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">static</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">MySearchView</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">SearchView</span> {</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">MySearchView</span>(Context context) { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>(context); } <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// The normal SearchView doesn't clear its search text when</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// collapsed, so we will do this for it.</span> <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onActionViewCollapsed</span>() { setQuery(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">""</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">super</span>.onActionViewCollapsed(); } } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onCreateOptionsMenu</span>(Menu menu, MenuInflater inflater) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Place an action bar item for searching.</span> MenuItem item = menu.add(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Search"</span>); item.setIcon(android.R.drawable.ic_menu_search); item.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM | MenuItem.SHOW_AS_ACTION_COLLAPSE_ACTION_VIEW); mSearchView = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> MySearchView(getActivity()); mSearchView.setOnQueryTextListener(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); mSearchView.setOnCloseListener(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>); mSearchView.setIconifiedByDefault(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>); item.setActionView(mSearchView); } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">onQueryTextChange</span>(String newText) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Called when the action bar search text has changed. Since this</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// is a simple array adapter, we can just have it do the filtering.</span> mCurFilter = !TextUtils.isEmpty(newText) ? newText : <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>; mAdapter.getFilter().filter(mCurFilter); <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">onQueryTextSubmit</span>(String query) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Don't care about this.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">boolean</span> <span class="hljs-title" style="box-sizing: border-box;">onClose</span>() { <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!TextUtils.isEmpty(mSearchView.getQuery())) { mSearchView.setQuery(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>; } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onListItemClick</span>(ListView l, View v, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> position, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">long</span> id) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Insert desired behavior here.</span> Log.i(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"LoaderCustom"</span>, <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Item clicked: "</span> + id); } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> Loader<List<AppEntry>> <span class="hljs-title" style="box-sizing: border-box;">onCreateLoader</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> id, Bundle args) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// This is called when a new Loader needs to be created. This</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// sample only has one Loader with no arguments, so it is simple.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> AppListLoader(getActivity()); } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoadFinished</span>(Loader<List<AppEntry>> loader, List<AppEntry> data) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Set the new data in the adapter.</span> mAdapter.setData(data); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// The list should now be shown.</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (isResumed()) { setListShown(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>); } <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> { setListShownNoAnimation(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>); } } <span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">onLoaderReset</span>(Loader<List<AppEntry>> loader) { <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Clear the data in the adapter.</span> mAdapter.setData(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>); }}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li><li style="box-sizing: border-box; padding: 0px 5px;">37</li><li style="box-sizing: border-box; padding: 0px 5px;">38</li><li style="box-sizing: border-box; padding: 0px 5px;">39</li><li style="box-sizing: border-box; padding: 0px 5px;">40</li><li style="box-sizing: border-box; padding: 0px 5px;">41</li><li style="box-sizing: border-box; padding: 0px 5px;">42</li><li style="box-sizing: border-box; padding: 0px 5px;">43</li><li style="box-sizing: border-box; padding: 0px 5px;">44</li><li style="box-sizing: border-box; padding: 0px 5px;">45</li><li style="box-sizing: border-box; padding: 0px 5px;">46</li><li style="box-sizing: border-box; padding: 0px 5px;">47</li><li style="box-sizing: border-box; padding: 0px 5px;">48</li><li style="box-sizing: border-box; padding: 0px 5px;">49</li><li style="box-sizing: border-box; padding: 0px 5px;">50</li><li style="box-sizing: border-box; padding: 0px 5px;">51</li><li style="box-sizing: border-box; padding: 0px 5px;">52</li><li style="box-sizing: border-box; padding: 0px 5px;">53</li><li style="box-sizing: border-box; padding: 0px 5px;">54</li><li style="box-sizing: border-box; padding: 0px 5px;">55</li><li style="box-sizing: border-box; padding: 0px 5px;">56</li><li style="box-sizing: border-box; padding: 0px 5px;">57</li><li style="box-sizing: border-box; padding: 0px 5px;">58</li><li style="box-sizing: border-box; padding: 0px 5px;">59</li><li style="box-sizing: border-box; padding: 0px 5px;">60</li><li style="box-sizing: border-box; padding: 0px 5px;">61</li><li style="box-sizing: border-box; padding: 0px 5px;">62</li><li style="box-sizing: border-box; padding: 0px 5px;">63</li><li style="box-sizing: border-box; padding: 0px 5px;">64</li><li style="box-sizing: border-box; padding: 0px 5px;">65</li><li style="box-sizing: border-box; padding: 0px 5px;">66</li><li style="box-sizing: border-box; padding: 0px 5px;">67</li><li style="box-sizing: border-box; padding: 0px 5px;">68</li><li style="box-sizing: border-box; padding: 0px 5px;">69</li><li style="box-sizing: border-box; padding: 0px 5px;">70</li><li style="box-sizing: border-box; padding: 0px 5px;">71</li><li style="box-sizing: border-box; padding: 0px 5px;">72</li><li style="box-sizing: border-box; padding: 0px 5px;">73</li><li style="box-sizing: border-box; padding: 0px 5px;">74</li><li style="box-sizing: border-box; padding: 0px 5px;">75</li><li style="box-sizing: border-box; padding: 0px 5px;">76</li><li style="box-sizing: border-box; padding: 0px 5px;">77</li><li style="box-sizing: border-box; padding: 0px 5px;">78</li><li style="box-sizing: border-box; padding: 0px 5px;">79</li><li style="box-sizing: border-box; padding: 0px 5px;">80</li><li style="box-sizing: border-box; padding: 0px 5px;">81</li><li style="box-sizing: border-box; padding: 0px 5px;">82</li><li style="box-sizing: border-box; padding: 0px 5px;">83</li><li style="box-sizing: border-box; padding: 0px 5px;">84</li><li style="box-sizing: border-box; padding: 0px 5px;">85</li><li style="box-sizing: border-box; padding: 0px 5px;">86</li><li style="box-sizing: border-box; padding: 0px 5px;">87</li><li style="box-sizing: border-box; padding: 0px 5px;">88</li><li style="box-sizing: border-box; padding: 0px 5px;">89</li><li style="box-sizing: border-box; padding: 0px 5px;">90</li><li style="box-sizing: border-box; padding: 0px 5px;">91</li><li style="box-sizing: border-box; padding: 0px 5px;">92</li><li style="box-sizing: border-box; padding: 0px 5px;">93</li><li style="box-sizing: border-box; padding: 0px 5px;">94</li><li style="box-sizing: border-box; padding: 0px 5px;">95</li><li style="box-sizing: border-box; padding: 0px 5px;">96</li><li style="box-sizing: border-box; padding: 0px 5px;">97</li><li style="box-sizing: border-box; padding: 0px 5px;">98</li><li style="box-sizing: border-box; padding: 0px 5px;">99</li><li style="box-sizing: border-box; padding: 0px 5px;">100</li><li style="box-sizing: border-box; padding: 0px 5px;">101</li><li style="box-sizing: border-box; padding: 0px 5px;">102</li><li style="box-sizing: border-box; padding: 0px 5px;">103</li><li style="box-sizing: border-box; padding: 0px 5px;">104</li><li style="box-sizing: border-box; padding: 0px 5px;">105</li><li style="box-sizing: border-box; padding: 0px 5px;">106</li><li style="box-sizing: border-box; padding: 0px 5px;">107</li><li style="box-sizing: border-box; padding: 0px 5px;">108</li><li style="box-sizing: border-box; padding: 0px 5px;">109</li><li style="box-sizing: border-box; padding: 0px 5px;">110</li><li style="box-sizing: border-box; padding: 0px 5px;">111</li><li style="box-sizing: border-box; padding: 0px 5px;">112</li><li style="box-sizing: border-box; padding: 0px 5px;">113</li><li style="box-sizing: border-box; padding: 0px 5px;">114</li><li style="box-sizing: border-box; padding: 0px 5px;">115</li><li style="box-sizing: border-box; padding: 0px 5px;">116</li><li style="box-sizing: border-box; padding: 0px 5px;">117</li><li style="box-sizing: border-box; padding: 0px 5px;">118</li><li style="box-sizing: border-box; padding: 0px 5px;">119</li><li style="box-sizing: border-box; padding: 0px 5px;">120</li><li style="box-sizing: border-box; padding: 0px 5px;">121</li><li style="box-sizing: border-box; padding: 0px 5px;">122</li><li style="box-sizing: border-box; padding: 0px 5px;">123</li><li style="box-sizing: border-box; padding: 0px 5px;">124</li><li style="box-sizing: border-box; padding: 0px 5px;">125</li><li style="box-sizing: border-box; padding: 0px 5px;">126</li><li style="box-sizing: border-box; padding: 0px 5px;">127</li><li style="box-sizing: border-box; padding: 0px 5px;">128</li><li style="box-sizing: border-box; padding: 0px 5px;">129</li><li style="box-sizing: border-box; padding: 0px 5px;">130</li><li style="box-sizing: border-box; padding: 0px 5px;">131</li><li style="box-sizing: border-box; padding: 0px 5px;">132</li><li style="box-sizing: border-box; padding: 0px 5px;">133</li><li style="box-sizing: border-box; padding: 0px 5px;">134</li><li style="box-sizing: border-box; padding: 0px 5px;">135</li><li style="box-sizing: border-box; padding: 0px 5px;">136</li><li style="box-sizing: border-box; padding: 0px 5px;">137</li><li style="box-sizing: border-box; padding: 0px 5px;">138</li><li style="box-sizing: border-box; padding: 0px 5px;">139</li><li style="box-sizing: border-box; padding: 0px 5px;">140</li><li style="box-sizing: border-box; padding: 0px 5px;">141</li><li style="box-sizing: border-box; padding: 0px 5px;">142</li><li style="box-sizing: border-box; padding: 0px 5px;">143</li><li style="box-sizing: border-box; padding: 0px 5px;">144</li><li style="box-sizing: border-box; padding: 0px 5px;">145</li><li style="box-sizing: border-box; padding: 0px 5px;">146</li></ul>强大的一逼！这下满技能，不解释，自己看。
4-4 进阶总结
通过前面基础实例、源码分析、进阶演示你会发现Loader的真的非常好用，非常牛逼，牛逼的我不想再解释啥了，自己体会吧。
PS：之前看见微博上有人讨论AsyncTaskLoader与AsyncTask的区别，这下彻底明朗了，看完源码我们再回过头来总结性的说说他们二者区别，如下：
好了，该撕逼的也撕了，该装逼的也装了，该分析的也分析了，该学习的也学到了，接下来就是看自己如何带着Loader去叱诧风云了。
【工匠若水 http://blog.csdn.net/yanbober 转载请注明出处。点我开始Android技术交流】
版权声明：本文为博主原创文章，未经博主允许不得转载。
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