Listview - empty list view doesn't show up

1<RelativeLayout ..."
2 xmlns:tools="..."
3 android:layout_width="match_parent"
4 android:layout_height="match_parent"
5 android:paddingBottom="@dimen/activity_vertical_margin"
6 android:paddingLeft="@dimen/activity_horizontal_margin"
7 android:paddingRight="@dimen/activity_horizontal_margin"
8 android:paddingTop="@dimen/activity_vertical_margin"
9 tools:context=".ListActivity" >
10
11 <ListView android:id="@id/android:list"
12android:layout_width="match_parent"
13android:layout_height="match_parent"
14android:background="#000fff"
15 />
16
17 <LinearLayout
18 android:id="@id/android:empty"
19 android:layout_width="fill_parent"
20 android:layout_height="fill_parent"
21 >
22 <Button
23 android:layout_width="match_parent"
24 android:layout_height="match_parent"
25 android:text="@string/click"
26 android:onClick="onClick"
27 />
28 </LinearLayout>

1<RelativeLayout xmlns:...
2 xmlns:tools= ...
3 android:id="@+id/RelativeLayout1"
4 android:layout_width="match_parent"
5 android:layout_height="match_parent"
6 android:orientation="vertical"
7 android:paddingBottom="@dimen/activity_vertical_margin"
8 android:paddingLeft="@dimen/activity_horizontal_margin"
9 android:paddingRight="@dimen/activity_horizontal_margin"
10 android:paddingTop="@dimen/activity_vertical_margin"
11 tools:context=".ListActivity" >
12
13 <ListView
14 android:id="@id/android:list"
15 android:layout_width="match_parent"
16 android:layout_height="match_parent"
17 android:layout_alignParentLeft="true"
18 android:layout_alignParentTop="true"
19 android:background="#000fff"
20 android:text="No data" />
21 <TextView
22android:id="@+id/android:empty"
23android:layout_width="match_parent"
24android:layout_height="match_parent"
25android:layout_alignParentLeft="true"
26 android:layout_alignParentTop="true"
27android:text="empty"/>
28
29
30
31</RelativeLayout>