设置按钮按下效果

select_btn_green_radius_17point5.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@drawable/btn_green_radius_17point5" android:state_pressed="false" />
<item android:drawable="@drawable/btn_green_radius_17point5_press" android:state_pressed="true" />
</selector>

btn_green_radius_17point5.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="#56BB7C" />
<corners android:radius="17.5dp" />
</shape>

btn_green_radius_17point5_press.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="#3A925B" />
<corners android:radius="17.5dp" />
</shape>