<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    
    <!-- 不是焦点-->
    <item android:state_focused="false" android:state_selected="false" android:state_pressed="false" android:drawable="@drawable/tab_camera_selected" />
    <item android:state_focused="false" android:state_selected="true" android:state_pressed="false" android:drawable="@drawable/tab_camera_unselected" />
    <!-- 焦点 -->
    <item android:state_focused="true" android:state_selected="false" android:state_pressed="false" android:drawable="@drawable/tab_camera_focus" />
    <item android:state_focused="true" android:state_selected="true" android:state_pressed="false" android:drawable="@drawable/tab_camera_focus" />
    <!-- 按住 -->
    <item android:state_pressed="true" android:drawable="@drawable/tab_camera_press" />
</selector>