title: Handling a UIBarButtonItem from a UITabBarController (UITabBarControllerDelegate)
body: <p>I'm new to this :-(.</p>
  
  <p>I have a pretty standard Tab Bar Controller to which I've added a UIButtonBarItem (I used the storyboard editor to do this). It all looks fine, but I don't know how to handle the "button press" event. I have established a delegate for the tab bar controller, so I can capture the "didSelectViewController" events (not that it seems to help :-).</p>
  
  <p>I think I'm missing something obvious.</p>