Android實用技巧.清單技巧（一）.EmptyView

之前做項目，清單頁資料為空時，空視圖是通過手動設定顯隐搞定，今天又學了一招，原來listView中可以添加空視圖

當adapter中item為空時，就會調用listView中的空視圖。

activity_list.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.administrator.androidbase.four.ListEmptyActivity">
    <ListView
        android:id="@+id/listView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">
    </ListView>
    <TextView
        android:id="@+id/empty"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="center"
        android:text="清單資料為空"/>
</RelativeLayout>
           

Listactivity

public class ListEmptyActivity extends Activity {
    ListView listView;
    private ArrayAdapter arrayAdapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_list_emtry);
        listView = (ListView)findViewById(R.id.listView);
        List<String> list = new ArrayList<>();
        list.add("頁面1");
        list.add("頁面2");
        list.add("頁面3");
        list.add("頁面4");
        list.add("頁面5");
        list.add("頁面6");
        list.add("頁面7");
        list.add("頁面8");
        list.add("頁面9");
        list.add("頁面10");
        arrayAdapter = new ArrayAdapter<>(this,R.layout.item_layout,R.id.text
                ,list);
        listView.setAdapter(arrayAdapter);
        listView.setEmptyView(findViewById(R.id.empty));
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                arrayAdapter = new ArrayAdapter<>(ListEmptyActivity.this,R.layout.item_layout,R.id.text
                        ,new ArrayList<>());
                listView.setAdapter(arrayAdapter);
            }
        });
    }

}