title: Switch views - UIViewController to UITabBarController
body: <p>I have made a very simple Navigation based app (UIViewController). The view has a single button on the Main RootViewController.</p>
  
  <p>Next, I made 2 classes: TabOneViewController, TabTwoViewController. All good. I then created a new Class TabBarViewController. I opened up the NIB file and dropped on a ``UITabBarController onto it. The two tabs it creates in it by default were assigned (respectively) to my TabOne and TabTwo view controllers.
  strong text
  Then in my TabBarViewController, I made an IBOutlet for a UITabBarController, synthesized it etc etc. I linked it up in Interface builder via the "files owner".</p>
  
  <p>In the RootViewController, I linked the button to my "pushView" method, and in this pushView method, I have the following code:</p>
  
  <pre><code>- (IBAction) pushView {
      TabBarViewController *controller = [[TabBarViewController alloc] init];
      [self.navigationController pushViewController:controller animated:YES];
      [controller release];
  }
  </code></pre>
  
  <p>The end result is it DOES push a view, but I cannot see the tab bar at the bottom, let alone any of the pages I've added to the controller.</p>
  
  <p>What am I doing wrong? Why can't I link it in IB?</p>