Android设置背景颜色渐变

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">  
    <item>        
        <shape>            
            <gradient                
                android:angle="270"                
                android:startColor="#3d4c66"    
                android:centerColor="#abb2bc"     
                android:endColor="#EDEDED" >            
            </gradient>        
        </shape>    
    </item>
</layer-list>