写在20111027：selector

假设现在需要设置一个ListView的ListItem点击的背景色，在drawable目录下创建下面的文件drawable/list_bg_selector.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="@color/clickcolor" />
    <item android:state_window_focused="true" android:drawable="@color/clickcolor" />
    <item android:drawable="@android:color/transparent" />
</selector>

实现按钮的点击效果
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true" android:drawable="@color/clickcolor" />
    <item android:state_focused="true" android:drawable="@color/clickcolor" />
    <item android:drawable="@android:color/transparent" />
</selector>