上中下布局,上下高度指定,中间自适应(左中右同理)

 1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:background="@drawable/bg_2"
 6     android:orientation="vertical" >
 7 
 8     <TextView
 9         android:id="@+id/tv1"
10         android:layout_width="match_parent"
11         android:layout_height="50dp"
12         android:background="#20Ff0000"
13         android:gravity="center"
14         android:text="@string/top"
15         android:textColor="#ffffff" />
16 
17     <TextView
18         android:id="@+id/v2"
19         android:layout_width="match_parent"
20         android:layout_height="match_parent"
21         android:layout_above="@+id/v3"
22         android:layout_below="@+id/tv1"
23         android:background="#7f00ff00"
24         android:gravity="center"
25         android:text="@string/middle"
26         android:textColor="#ffffff" />
27 
28     <TextView
29         android:id="@+id/v3"
30         android:layout_width="match_parent"
31         android:layout_height="50dp"
32         android:layout_alignParentBottom="true"
33         android:background="#700000ff"
34         android:gravity="center"
35         android:text="@string/bottom"
36         android:textColor="#ffffff" />
37 
38 </RelativeLayout>