<?xml version="1.0" encoding="utf-8"?> 
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" > 
    <!-- 边框阴影部分 --> 
    <!-- 相对边框的Offset设置(android:left, top, right, bottom) --> 
    <item 
        android:left="0dp" 
        android:top="0dp" 
        android:right="0dp" 
        android:bottom="0dp"> 
        <shape android:shape="rectangle" > 
            <gradient 
                android:angle="270" 
                android:startColor="@color/colorACardShadow"
                android:centerColor="@color/colorACardShadow"
                android:endColor="@color/colorACardShadow"/> 
            <corners android:radius="?attr/borderCornerRadius" />
        </shape> 
    </item>
    <!-- 边框部分 -->
    <item 
        android:left="0dp" 
        android:top="0dp" 
        android:right="1dp" 
        android:bottom="2dp"> 
        <shape android:shape="rectangle" > 
            <gradient 
                android:angle="270" 
                android:startColor="@color/colorACardFrame"
                android:centerColor="@color/colorACardFrame"
                android:endColor="@color/colorACardFrame"/> 
            <corners android:radius="?attr/borderCornerRadius" />
        </shape> 
    </item>
    <!-- 背景主体部分 -->
    <item
        android:left="2dp" 
        android:top="2dp" 
        android:right="3dp" 
        android:bottom="3dp"> 
        <shape android:shape="rectangle" > 
            <gradient
                android:type="linear"
                android:angle="90"
                android:startColor="@color/colorACardBackgroung"
                android:centerColor="@color/colorACardBackgroung"
                android:endColor="@color/colorACardBackgroung"/> 
            <corners android:radius="?attr/borderCornerRadius" />
        </shape> 
    </item> 
</layer-list>
