ScorllView嵌套ListView时动态设置高度时的问题

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一、今天遇到了ListView在自适应扩充高度时候出现的问题.
1.网上查的很多,都是说写个Util类,来自扩充Listview的高度.但是,一旦这个Listview是嵌套在ScorllView里的,那么ListView和ScorllView的滑动会冲突.导致Listview只显示一小行.
最初的时候,我是给Listview的Adapter设置了Minheight.但是Item里的文本(TextView一旦多了.)就会导致显示文字不全.
在这里要说明下,要想全部高度显示,textview和父布局文件必须:wrap_content

废话不多说了,上代码了.
网上有很多说明了,但是作为小白,可能不知道怎么做.
一、,就是要重新自定义一个Listview.继承ListView.重写其中的onMeasure方法.

因为ListView扩展时因为很多原因,可能达不到完美的效果.

*在写第三个MyListView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
}的时候,AS会提示API兼容的问题.*
自动调整下就OK了.

<code class="hljs java has-numbering"><span class="hljs-keyword">import</span> android.content.Context;<span class="hljs-keyword">import</span> android.util.AttributeSet;<span class="hljs-keyword">import</span> android.widget.ListView;<span class="hljs-keyword">public</span> <span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">MyListView</span> <span class="hljs-keyword">extends</span> <span class="hljs-title">ListView</span>{</span>    <span class="hljs-keyword">public</span> <span class="hljs-title">MyListView</span>(Context context) {        <span class="hljs-keyword">super</span>(context);    }    <span class="hljs-keyword">public</span> <span class="hljs-title">MyListView</span>(Context context, AttributeSet attrs) {        <span class="hljs-keyword">super</span>(context, attrs);    }    <span class="hljs-keyword">public</span> <span class="hljs-title">MyListView</span>(Context context, AttributeSet attrs, <span class="hljs-keyword">int</span> defStyleAttr) {        <span class="hljs-keyword">super</span>(context, attrs, defStyleAttr);    }    <span class="hljs-keyword">public</span> <span class="hljs-title">MyListView</span>(Context context, AttributeSet attrs, <span class="hljs-keyword">int</span> defStyleAttr, <span class="hljs-keyword">int</span> defStyleRes) {        <span class="hljs-keyword">super</span>(context, attrs, defStyleAttr, defStyleRes);    }    <span class="hljs-annotation">@Override</span>    <span class="hljs-keyword">protected</span> <span class="hljs-keyword">void</span> <span class="hljs-title">onMeasure</span>(<span class="hljs-keyword">int</span> widthMeasureSpec, <span class="hljs-keyword">int</span> heightMeasureSpec) {        <span class="hljs-keyword">int</span> expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> <span class="hljs-number">2</span>,                MeasureSpec.AT_MOST);        <span class="hljs-keyword">super</span>.onMeasure(widthMeasureSpec, expandSpec);    }}</code>

这是在ListViewUtil里写的方法.

<code class="hljs java has-numbering"> <span class="hljs-javadoc">/**     * 动态设置ListView的高度     *     *<span class="hljs-javadoctag"> @param</span> listView     */</span>    <span class="hljs-keyword">public</span> <span class="hljs-keyword">static</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setListViewHeightBasedOnChildren</span>(ListView listView, ListAdapter adapter) {        <span class="hljs-keyword">if</span> (listView == <span class="hljs-keyword">null</span>) <span class="hljs-keyword">return</span>;        <span class="hljs-keyword">if</span> (adapter == <span class="hljs-keyword">null</span>) {            <span class="hljs-keyword">return</span>;        }        <span class="hljs-keyword">int</span> totalHeight = <span class="hljs-number">0</span>;        <span class="hljs-keyword">for</span> (<span class="hljs-keyword">int</span> i = <span class="hljs-number">0</span>; i < adapter.getCount(); i++) {            View listItem = adapter.getView(i, <span class="hljs-keyword">null</span>, listView);            listItem.measure(<span class="hljs-number">0</span>, <span class="hljs-number">0</span>);<span class="hljs-comment">//计算每项   Item的高度</span>            totalHeight += listItem.getMeasuredHeight();        }        ViewGroup.LayoutParams params = listView.getLayoutParams();        params.height = totalHeight + (listView.getDividerHeight() * (adapter.getCount() - <span class="hljs-number">1</span>));        <span class="hljs-comment">//循环完之后,要计算出getDividerHeight(空白处占得height)   才是Listview的高度</span>        listView.setLayoutParams(params);    }</code>

然后是最后一步:
一定要在获取数据后:

<code class="hljs cs has-numbering"> adapter = <span class="hljs-keyword">new</span> MyListAdapter(<span class="hljs-keyword">this</span>, CommentmData);            mListView.setAdapter(adapter);  ListViewUtil.setListViewHeightBasedOnChildren(mListView, adapter);</code>

还可能牵扯到更新Adapter后的数据变动,也要调用该方法.

<code class="hljs java has-numbering">ListViewUtil.setListViewHeightBasedOnChildren(mListView, adapter);<span class="hljs-javadoc">mListView 就是你布局里那个Listviewadapter就是适配Listview的Adapter</span></code>
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