13-开关按钮Switch

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_checked="true" android:drawable="@drawable/switch_on"/>
    <item android:drawable="@drawable/switch_off"/>
</selector>

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval" android:layout_height="wrap_content" android:layout_width="wrap_content">

    <size
        android:width="40dp"
        android:height="40dp"/>
    <solid
        android:color="@color/white"/>
</shape>