Wrong background selected when focus in LinearLayout's children
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I have a linearLayout with buttons as its children. I need the button backgrounds to change when they get focus. The buttons are focusable in touch mode.

I have set the following selector xml to the buttons. 

    <selector xmlns:android="http://schemas.android.com/apk/res/android">
        <item android:state_focused="true"  
               android:drawable="@drawable/tile_focused" />
        <item android:drawable="@drawable/tile" /> <!-- default -->
    </selector>

The problem is that when I set focus to any one button, all button's backgrounds change to "tile_focused". 
I guess the problem is in the selector xml. What is wrong here?