Android设置Button各种状态下背景改变

   写一段代码如下，保存为文件button_background_change.xml至drawable文件夹

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="false" android:drawable="@drawable/search_btn_background"/>
    <item android:state_pressed="true"  android:drawable="@drawable/search_btn_background_onclick"/>
</selector>

Button使用的时候给设置android:background="@drawable/button_background_change"

        <Button
            android:id="@+id/button1"
            android:layout_width="0dp"
            android:layout_height="40dp"
            android:layout_weight="1"
            android:background="@drawable/button_background_change"
            android:text="@string/serach" />