title: UINavigationController from UIViewController
body: <p>I currently have this workflow in a tab based app:</p>
  
  <p>Tab1 loads...</p>
  
  <pre><code>ViewOne : UIViewController
    &gt;&gt; 
      PickerView : UIViewController
      &gt;&gt; 
         DetailView : UIViewController
  </code></pre>
  
  <p>">>" means loads based on user action.  I'd like navigation bars on PickerView and DetailView.  PickerView just needs a cancel button in the top left of its nav bar.  DetailView needs the normal navbar back button.  I already have PickerView's nav bar wired up through IB and working.  I'm not sure what to do with PickerView's nav bar.  </p>
  
  <p>PickerView is also loaded from Tab2, who's main view starts as a UINavigationController.  PickerView's nav bar works fine in that case.</p>
  
  <p>ViewOne should not have a navigation bar.</p>
  
  <p>Any ideas?</p>