title: How to add a tab bar item to UITabBarController without a view controller?
body: <p>In my iPad app, I have a UITabBarController at the bottom with a bunch of view controllers associated to a bunch of tabs. I would like to have a tab that shows a pop over when the tab is touched. I know how to use the UIPopoverController, but I don't know how to add a tab to a UITabBarController without giving the tab bar controller a UIViewController. </p>
  
  <p>Any suggestions on how to do this? </p>
  
  <p>Thanks.</p>
  
  <p>Here is the code that I have to show the pop over. (<a href="https://stackoverflow.com/questions/4405350/how-can-i-have-a-popover-come-from-a-tab-instead-of-a-view">Source</a>)</p>
  
  <pre><code>CGFloat tabBarHeight = self.tabBarController.tabBar.bounds.size.height;
  CGRect rect = CGRectMake(0, 0, tabBarHeight, tabBarHeight);
  [popoverController presentPopoverFromRect:rect 
      inView:self.tabBarController.tabBar 
      permittedArrowDirections:UIPopoverArrowDirectionDown animated:YES];
  </code></pre>