Android---ListView只显示一行的解决方案

Android编程中,ScrollView嵌套ListView时,会无法正确的计算ListView的大小。解决的办法有如下两种:

解决方案1:直接把包含ListView控件的ScrollView控件从布局文件中去除,留下ListView控件,这是最简单快捷的解决办法,如果一定要在ScrollView中包含ListView,则参考解决方案2:

去除Scroll之前的XML:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"   
    xmlns:tools="http://schemas.android.com/tools"   
    android:layout_width="match_parent"   
    android:layout_height="match_parent"   
    android:background="#FFFFFF"   
    android:orientation="vertical" >   
    <ScrollView   
        android:layout_width="match_parent"   
        android:layout_height="match_parent" >   
        <LinearLayout   
            android:layout_width="match_parent"   
            android:layout_height="match_parent" >   
            <ListView   
                android:id="@+id/test_listView"   
                android:layout_width="match_parent"   
                android:layout_height="match_parent"   
                android:fadingEdge="vertical"/>   
        </LinearLayout>   
    </ScrollView>   
</LinearLayout> 

去除ScrollView之后的XML:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"   
    xmlns:tools="http://schemas.android.com/tools"   
    android:layout_width="match_parent"   
    android:layout_height="match_parent"   
    android:background="#FFFFFF"   
    android:orientation="vertical" >   
        <LinearLayout   
            android:layout_width="match_parent"   
            android:layout_height="match_parent" >   
            <ListView   
                android:id="@+id/test_listView"   
                android:layout_width="match_parent"   
                android:layout_height="match_parent"   
                android:fadingEdge="vertical"  />   
        </LinearLayout>   
</LinearLayout>   

解决方案2:通过代码,根据当前的ListView的列表子项计算列表的高度:

public class MainActivity extends Activity {   
    private ListView listView;  
    private String[] adapterData = new String[] { "标题1", "标题2", "标题3"}; 
    
   @Override   
    protected void onCreate(Bundle savedInstanceState) {   
        super.onCreate(savedInstanceState);   
        setContentView(R.layout.mainActivity);   
        listView = (ListView) findViewById(R.id.test_listView);   
        listView.setAdapter(new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,adapterData));   
        fixListViewHeight(listView);   
    }   
   
    public void fixListViewHeight(ListView listView) {   
        // 如果没有设置数据适配器,则ListView没有子项,返回。  
        ListAdapter listAdapter = listView.getAdapter();  
        int totalHeight = 0;   
        if (listAdapter == null) {   
            return;   
        }   
        for (int index = 0, len = listAdapter.getCount(); index < len; index++) {     
            View listViewItem = listAdapter.getView(index , null, listView);  
            // 计算子项View 的宽高   
            listViewItem.measure(0, 0);    
            // 计算所有子项的高度和
            totalHeight += listViewItem.getMeasuredHeight();    
        }   
   
        ViewGroup.LayoutParams params = listView.getLayoutParams();   
        // listView.getDividerHeight()获取子项间分隔符的高度   
        // params.height设置ListView完全显示需要的高度    
        params.height = totalHeight+ (listView.getDividerHeight() * (listAdapter.getCount() - 1));   
        listView.setLayoutParams(params);   
    }   
}   

原文链接: http://jingyan.baidu.com/article/afd8f4de4695af34e386e969.html


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转载自blog.csdn.net/huazicomeon/article/details/61202266