Android selector应用

--------- drawable保存为.xml
<?xml version="1.0" encoding="utf-8"?>
<selector
xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true" android:drawable="@drawable/bt13" />
<item android:drawable="@drawable/bt12" />
</selector>

---------main.xml button设计
<Button
android:id="@+id/Button1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1.0"
android:background="@drawable/buttontype"
android:text="点击设计" />