title: Change contentSizeForViewInPopover on navigationController push on iOS
body: <p>I have a UIPopoverController with navigationController and bunch of subviews. The size of the popover is set just before it's shown like this:</p>
  
  <pre><code>[self.myPopover setPopoverContentSize:CGSizeMake(320, 500)];
  </code></pre>
  
  <p>That works fine. The popover is shown with adjusted size. When another view is pushed on navigation stack the size of a popover is set again - need different height - in viewWillAppear method:</p>
  
  <pre><code>self.contentSizeForViewInPopover = CGSizeMake(320, 700);
  </code></pre>
  
  <p>This also works fine. When I go back to a previous view the size does not change.</p>
  
  <p>I added the same call in viewWillAppear in first view but the view does not resize.</p>
  
  <p>How can I manage resizing of popover when navigating between views?</p>