title: willHideViewController not called when switching to view in portrait mode
body: <p>My iPad app uses the standard UISplitViewController. My problem is, if I </p>
  
  <ul>
  <li>Rotate to portrait, I put a Popover button for the Master list - Fine</li>
  <li>Select an item via the popover, that changes the detailview (This uses a <code>prepareForSegue</code> which sets <code>self.splitViewController.delegate = newViewDetailViewController;</code></li>
  <li>The resulting detailview is now missing a popoverbutton. If I rotate to landscape, the master list appears. If I then again rotate to portrait, a popoverbutton appears.</li>
  </ul>
  
  <p>So - How can I ensure <code>willHideViewController</code> will be called on <code>viewDidLoad</code>, for example?
  I can detect what the orientation is, but I still need the barbuttonitem and popovercontroller needed in</p>
  
  <p><code>- (void)splitViewController:(UISplitViewController *)splitController willHideViewController:(UIViewController *)viewController withBarButtonItem:(UIBarButtonItem *)barButtonItem forPopoverController:(UIPopoverController *)popoverController</code></p>
  
  <p>For now I am following Apples MultipleDetailView example as suggested <a href="https://stackoverflow.com/questions/7885625/ios-uisplitviewcontrollers-popover-controller-button-disappear-after-pushing-ne">here</a>.</p>
  
  <p>But since I am having multiple MasterControllers as well, it's a real hassle to store (a static) pointer to the popoverbutton item and setting it every time I push a level on my masterview controller.</p>
  
  <p>Hopefully, someone has a good way of solving this problem :-)</p>