Android开发中遇到的问题

来源：互联网发布：nginx修改403页面编辑：程序博客网时间：2024/06/05 16:49

本文转自“唯鹿”的博客，地址：

http://blog.csdn.net/qq_17766199/article/details/52661363

1.App的首次安装。

问题描述：在我们安装完成一个app时，在安装界面直接点击打开。我们进入了app的首页，这时我们按home键返回桌面，再点击应用图标，会发现没有直接进入首页，而是先进入了app的闪屏页，在进入首页。重复这一步一直如此。这时我们按back键返回，发现没有直接退回桌面，而是返回到之前打开的多个首页。但是如果一开始安装完我们不是直接打开，而是在桌面点击应用进入就不会这样了。

奇奇怪怪~~

记得当时我在应用市场下载了部分应用，也有一些有同样的问题。但是有些虽然重复打开，但双击退出程序将整个重复打开的关闭了。这确实也是一种方法，但是觉得不是最合理。

解决方法：
https://code.google.com/p/android/issues/detail?id=2373#c40

http://stackoverflow.com/questions/3042420/home-key-press-behaviour/4782423#4782423

我贴一下代码

if (!isTaskRoot()) {            Intent intent = getIntent();            String action = intent.getAction();            if (intent.hasCategory(Intent.CATEGORY_LAUNCHER) && action != null && action.equals(Intent.ACTION_MAIN)) {                finish();                return;            }        }

2.Android自定义CheckBox

问题描述：曾经写过一个自定义CheckBox，结果运行在4.1的手机上消失不见了。。。你说郁闷不。写法如下：

<CheckBox      android:id="@+id/check_box"      style="@style/MyCheckBox"      android:layout_width="wrap_content"      android:layout_height="match_parent"/>

<style name="MyCheckBox" parent="Widget.AppCompat.CompoundButton.CheckBox">        <item name="android:button">@drawable/checkbox_selector</item></style>

<?xml version="1.0" encoding="utf-8"?><selector xmlns:android="http://schemas.android.com/apk/res/android">    <item android:drawable="@drawable/icon_on" android:state_checked="true"/> <!-- 设置选中图片 -->    <item android:drawable="@drawable/icon_off" android:state_checked="false"/> <!-- 设置未选中图片 --></selector>

写法没有什么问题吧，但是就是不显示，凭空消失。当然如果我加上文字，就出来了，但是文字图片重叠。。。

最后谷歌出了原因：大致是说4.1.2版本中CompoundButton没有getCompoundPaddingXX。两个版本的计算方式不一样，4.1.2以上版本绘制文字时，会把图片的宽度和paddingXX的宽度加上，而4.1.2版本只计算设置的paddingLeft。

知道了原因，解决方法：

<style name="MyCheckBox" parent="Widget.AppCompat.CompoundButton.CheckBox">        <item name="android:button">@null</item>        <item name="android:paddingLeft">0dp</item>        <item name="android:drawableLeft">@drawable/checkbox_selector</item></style>

RecyclerView Bug

问题描述：这个是在友盟的错误分析中报的，错误信息如下：

java.lang.IndexOutOfBoundsException: Inconsistency detected. Invalid view holder adapter positionViewHolder{42fb7f40 position=11 id=-1, oldPos=-1, pLpos:-1 no parent}    at android.support.v7.widget.RecyclerView$Recycler.validateViewHolderForOffsetPosition(RecyclerView.java:4801)    at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4932)    at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4913)    at android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2029)    at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1414)    at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1377)    at android.support.v7.widget.LinearLayoutManager.scrollBy(LinearLayoutManager.java:1193)    at android.support.v7.widget.LinearLayoutManager.scrollVerticallyBy(LinearLayoutManager.java:1043)    at android.support.v7.widget.RecyclerView.scrollByInternal(RecyclerView.java:1552)    at android.support.v7.widget.RecyclerView.onTouchEvent(RecyclerView.java:2649)    at android.view.View.dispatchTouchEvent(View.java:7706)    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2224)    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1954)    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)    at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:2074)    at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1521)    at android.app.Activity.dispatchTouchEvent(Activity.java:2569)    at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:2022)    at android.view.View.dispatchPointerEvent(View.java:7886)    at android.view.ViewRootImpl$ViewPostImeInputStage.processPointerEvent(ViewRootImpl.java:3967)    at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:3846)    at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3412)    at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3462)    at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3431)    at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:3538)    at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3439)    at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:3595)    at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3412)    at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3462)    at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3431)    at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3439)    at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3412)    at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:5552)    at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:5532)    at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:5503)    at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:5632)    at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:185)    at android.view.InputEventReceiver.nativeConsumeBatchedInputEvents(Native Method)    at android.view.InputEventReceiver.consumeBatchedInputEvents(InputEventReceiver.java:176)    at android.view.ViewRootImpl.doConsumeBatchedInput(ViewRootImpl.java:5605)    at android.view.ViewRootImpl$ConsumeBatchedInputRunnable.run(ViewRootImpl.java:5651)    at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761)    at android.view.Choreographer.doCallbacks(Choreographer.java:574)    at android.view.Choreographer.doFrame(Choreographer.java:542)    at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747)    at android.os.Handler.handleCallback(Handler.java:733)    at android.os.Handler.dispatchMessage(Handler.java:95)    at android.os.Looper.loop(Looper.java:136)    at android.app.ActivityThread.main(ActivityThread.java:5162)    at java.lang.reflect.Method.invokeNative(Native Method)    at java.lang.reflect.Method.invoke(Method.java:515)    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:789)    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:602)

从上面可以看到并没有报到我们自己的代码里面来，这就很尴尬了。老办法谷歌，找到了Drakeet大神的一篇博客，说到了我的心坎里。

重现的方法是：使用 RecyclerView 加官方下拉刷新的时候，如果绑定的 List 对象在更新数据之前进行了 clear，而这时用户紧接着迅速上滑 RV，就会造成崩溃，而且异常不会报到你的代码上，属于RV内部错误。初次猜测是，当你 clear 了 list 之后，这时迅速上滑，而新数据还没到来，导致 RV 要更新加载下面的 Item 时候，找不到数据源了，造成 crash.

真是一样一样的，那么解决方法大神也提供了，就是在刷新，也就是 clear 的同时，让 RecyclerView 暂时不能够滑动，之后再允许滑动即可。代码就是在 RecyclerView 初始化的时候加上是否在刷新进而拦截手势：

mRecyclerView.setOnTouchListener(        new View.OnTouchListener() {            @Override            public boolean onTouch(View v, MotionEvent event) {                if (mIsRefreshing) {                    return true;                } else {                    return false;                }            }        });

当然如果觉得刷新时不能滑动可以用这种方案：

public class WrapContentLinearLayoutManager extends LinearLayoutManager {    //... constructor    @Override    public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) {        try {            super.onLayoutChildren(recycler, state);        } catch (IndexOutOfBoundsException e) {            Log.e("probe", "meet a IOOBE in RecyclerView");        }    }}

使用：

RecyclerView recyclerView = (RecyclerView)findViewById(R.id.recycler_view);recyclerView.setLayoutManager(new WrapContentLinearLayoutManager(activity, LinearLayoutManager.HORIZONTAL, false));

补充：但是这里要注意的是，禁止 RecycleView “下拉刷新” 和 “加载更多” 同时执行。否则会报：

java.lang.IllegalStateException: Added View has RecyclerView as parent but view is not a real child. Unfiltered index:0    at android.support.v7.widget.RecyclerView$LayoutManager.addViewInt(RecyclerView.java:7048)    at android.support.v7.widget.RecyclerView$LayoutManager.addView(RecyclerView.java:7012)    at android.support.v7.widget.RecyclerView$LayoutManager.addView(RecyclerView.java:7000)    at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1428)    at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1377)    at android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:578)    at com.jingzhao.shopping.customview.WrapContentLinearLayoutManager.onLayoutChildren(WrapContentLinearLayoutManager.java:27)<---这里    at android.support.v7.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:3260)    at android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.java:3069)    at android.support.v7.widget.RecyclerView.onLayout(RecyclerView.java:3518)    at android.view.View.layout(View.java:15697)    at android.view.ViewGroup.layout(ViewGroup.java:5050)    at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1077)    at android.view.View.layout(View.java:15697)    at android.view.ViewGroup.layout(ViewGroup.java:5050)    at android.support.v4.widget.SwipeRefreshLayout.onLayout(SwipeRefreshLayout.java:598)    at android.view.View.layout(View.java:15697)    at android.view.ViewGroup.layout(ViewGroup.java:5050)    at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703)    at android.widget.LinearLayout.layoutHorizontal(LinearLayout.java:1692)    at android.widget.LinearLayout.onLayout(LinearLayout.java:1468)    at android.view.View.layout(View.java:15697)    at android.view.ViewGroup.layout(ViewGroup.java:5050)    at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1077)    at android.view.View.layout(View.java:15697)    at android.view.ViewGroup.layout(ViewGroup.java:5050)    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:579)    at android.widget.FrameLayout.onLayout(FrameLayout.java:514)    at android.view.View.layout(View.java:15697)    at android.view.ViewGroup.layout(ViewGroup.java:5050)    at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703)    at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1557)    at android.widget.LinearLayout.onLayout(LinearLayout.java:1466)    at android.view.View.layout(View.java:15697)    at android.view.ViewGroup.layout(ViewGroup.java:5050)    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:579)    at android.widget.FrameLayout.onLayout(FrameLayout.java:514)    at android.view.View.layout(View.java:15697)    at android.view.ViewGroup.layout(ViewGroup.java:5050)    at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2232)    at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1984)    at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1163)    at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6190)    at android.view.Choreographer$CallbackRecord.run(Choreographer.java:773)    at android.view.Choreographer.doCallbacks(Choreographer.java:586)    at android.view.Choreographer.doFrame(Choreographer.java:556)    at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:759)    at android.os.Handler.handleCallback(Handler.java:739)    at android.os.Handler.dispatchMessage(Handler.java:95)    at android.os.Looper.loop(Looper.java:159)    at android.app.ActivityThread.main(ActivityThread.java:5540)    at java.lang.reflect.Method.invoke(Native Method)    at java.lang.reflect.Method.invoke(Method.java:372)    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:964)    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:759)

可以做类似的处理：

if(swipeRefreshLayout.isRefreshing()){    return;}

4.一些注意点

（1）平时为了给apk瘦身，我们会对图片进行有损或无损的压缩。那我平时有用到的一个有损压缩网站tinypng，但是切记我们的9图不要压缩，不然会有问题。（这里顺便分享一个做9图的在线工具http://inloop.github.io/shadow4android/）

（2）Android的透明主题需谨慎使用。

（3）for循环不要把获得数量的代码写在循环当中：for(int i = 0; i <= list.size(); i ++)

（4）ListView的如果其宽度或高度被设置为wrap_content，会有性能等问题。参见：http://stackoverflow.com/questions/4270278/layout-width-of-a-listview

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