button selector 样式
<selector xmlns:android="http://schemas.android.com/apk/res/android">
??? <item android:state_pressed="false" android:state_focused="false" android:drawable="@drawable/list_normal_ui2" />
??? <item android:state_pressed="false" android:state_focused="true" android:drawable="@drawable/list_focused_ui2" />
??? <item android:state_pressed="true" android:state_focused="false" android:drawable="@drawable/list_pressed_ui2" />
??? <item android:state_pressed="true" android:state_focused="true" android:drawable="@drawable/list_pressed_ui2" />
</selector>
点击，获得焦点，正常~
