selector加layer-list的用法

先看效果图:

xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_checked="false">
        <shape>
            <corners android:radius="5dp"/>
            <solid android:color="@color/zi_be"/>
        shape>
    item>
    <item android:state_checked="true">
        <layer-list>
            <item>
                <shape>
                    <corners android:radius="5dp" />
                    <solid android:color="@color/bai_ff" />
                    <stroke android:width="1dp" android:color="@color/zi_be" />
                shape>
            item>
            
            <item android:right="9dp">
                <bitmap android:src="@drawable/grade3" android:gravity="center_vertical|right" />
            item>
        layer-list>
    item>
selector>