title: How to make an android imagebutton object switch images
body: <p>I am building a board game for the Android platform.</p>
  
  <p>The game has a main screen with a row of buttons that the user uses to indicate how they want to play the game (1 player, 2 player, wi-fi, and network).</p>
  
  <p>I would like the know the most effective way of displaying that a selection was chosen by switching images. I am currently using <code>ImageButton</code> objects to display these options. When the user selects a mode by clicking on it, the image that was there should be replaced by one that is darker. I know how to do this using <code>android:state_pressed</code> so that for the duration of the click, another image shows. However what I need is for the other image to replace the original once the button is clicked, not just while the click is held, until another button is clicked, at which point the button should revert to displaying the first image again. Can someone tell me how to do this please?</p>