<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:state_checked="false" android:drawable="@drawable/radio_button_unselect"/>  
    <item android:state_checked="true"  android:drawable="@drawable/radio_button_selected"/>  
    <item android:state_selected="true"  android:drawable="@drawable/radio_button_selected"/>  
    <item android:state_pressed="true"  android:drawable="@drawable/radio_button_selected"/>      
</selector>