xml for theme select menu (see select time menu if you don't know how to use it)

context_theme.xml

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android" >
    <group android:checkableBehavior="single">
	    <item android:id="@+id/theme1" android:title="Amazon" />
		<item android:id="@+id/theme2" android:title="Colorful" />
		<item android:id="@+id/theme3" android:title="Sunshine" />
		<item android:id="@+id/theme4" android:title="Twilight" />
	</group>
</menu>