Android Programming: The Big Nerd Ranch Guide, 2nd Edition

Layer List Drawables

BeatBox is looking good. You now have round buttons and they visually respond to presses. Time for something a little more advanced.

Layer list drawables allow you to combine two XML drawables into one. Armed with this tool, add a dark ring around your button when in the pressed state.

Listing 21.7  Using a layer list drawable (res/drawable/button_beat_box_pressed.xml)

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