title: Multiple Hierarchy levels with navigation Controller
body: <p>I'm trying to get multiple levels of hierarchy working
  with Navigation Controllers.  I have 3 levels of hierarchy and
  I can move down through the levels of hierarchy, but I can
  only go back one level and not two levels, back to the starting
  view.</p>
  
  <p>I start by creating a navigation controller for View #1 and push the next
  view, View #2,  onto it.  Then I add the navigation controller to the 
  subview of the window in didSelectRowAtIndexPath.  Clicking on 
  a table row in View #1 , takes me to the next hiearchy level View #2.</p>
  
  <p>This next hiearchy level view is also a table view.  Here is where
  I think the problem occurs. I create another navigation controller
  and push View #3 onto it in didSelectRowAtIndexPath in the View 
  Controller for View #2.  Clicking on a table row in View #2 takes
  me to View #3.  But when I use the back button to go back to View #2,
  I go back to an empty view, and not the real View #2.</p>
  
  <ol>
  <li><p>Do I only need one navigation controller to handle 3 levels of
  hiearchy instead of two navigation controllers?</p></li>
  <li><p>If #1 is yes, then how do I pass the navigation controller to view #2's
  controller so that I can push View #3 onto the navigation controller?</p></li>
  <li><p>Or do I need to push all three views onto the navigation controller
  in View #1?</p></li>
  <li><p>Or...?</p></li>
  </ol>
  
  <p>Thanks in advance,</p>
  
  <p>Jim</p>