android 描边

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

    <item >
        <shape >
            <!-- 描边-->
            <stroke android:width="2px" android:color="@color/stroke_color"/>
        </shape>
    </item>

    <item  android:bottom="2px" android:top="2px" android:left="2px" android:right="2px">
        <shape>
            <solid android:color="@color/white" />
        </shape>
    </item>

</layer-list>