ListView中不显示HeaderView

2015-03-28 07:36:29 697 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

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ListView中加了头和尾后不显示HeaderView。当ListView高度为精确值时（dp）没问题。但当为match_parent和wrap_content时就只能看到尾了，看不到头（头成是空白了），请各位帮忙看一下。
activity_main.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:orientation="vertical" >

	<ListView 

	    android:id="@+id/lv"

	    android:layout_width="match_parent"

    	android:layout_height="match_parent" >

	    

	</ListView>

</LinearLayout>

listfooter.xml：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:id="@+id/ll_listfooter"

    android:layout_width="match_parent"

    android:layout_height="wrap_content"

    android:orientation="vertical" >



    <Button

        android:id="@+id/btn_load_more"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="Loading" />



</LinearLayout>

MainActivity.java

public class MainActivity extends Activity {

	ListView lv = null;

	@Override

	protected void onCreate(Bundle savedInstanceState) {

		super.onCreate(savedInstanceState);

		setContentView(R.layout.activity_main);

		View listfooter = LayoutInflater.from(this).inflate(R.layout.listfooter, null);

		lv = (ListView) this.findViewById(R.id.lv);

		lv.addFooterView(listfooter, null, true);

		lv.addHeaderView(listfooter, null, true);

		lv.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_expandable_list_item_1,getData()));

		Toast.makeText(this, " "+lv.getCount(), Toast.LENGTH_SHORT).show();

	}

	private List<String> getData(){

        

        List<String> data = new ArrayList<String>();

        data.add("测试数据1");

        data.add("测试数据2");

        data.add("测试数据3");

        data.add("测试数据4");

         

        return data;

    }

	@Override

	public boolean onCreateOptionsMenu(Menu menu) {

		// Inflate the menu; this adds items to the action bar if it is present.

		getMenuInflater().inflate(R.menu.main, menu);

		return true;

	}



	@Override

	public boolean onOptionsItemSelected(MenuItem item) {

		// Handle action bar item clicks here. The action bar will

		// automatically handle clicks on the Home/Up button, so long

		// as you specify a parent activity in AndroidManifest.xml.

		int id = item.getItemId();

		if (id == R.id.action_settings) {

			return true;

		}

		return super.onOptionsItemSelected(item);

	}

}