title: How to present UIImagePickerController in popover from a popover?
body: <p>Consider the following scenario on an iPad app:</p>
  
  <p>The app is showing a fullscreen <code>UINavigationController</code> with some content.
  When pressing a navigationbar button, a popover is shown (that shows a table with various controls).
  A table cell in that popover offers to pick a photo from the device's photo library. For this, the <code>UIImagePickerController</code> shall be used.</p>
  
  <p>According to the iOS HIG, the <code>UIImagePickerController</code> must be shown as a popover on the iPad. </p>
  
  <p><strong>Question:</strong>
  What is the best way to present the <code>UIImagePickerController</code> in a popover in the above situation? (ie. from a popover)</p>
  
  <p>Clearly I cannot show the <code>UIImagePickerController</code> popover from another popover.</p>
  
  <p>Should I show the first popover content in a form sheet, allowing the <code>UIImagePickerController</code> to open in its own popover?</p>
  
  <p>Or: When the button to show <code>UIImagePickerController</code> is pressed, should I dismiss the popover and show <code>UIImagePickerController</code> in a new popover from the same navigationbar button? At first glace this looks like an odd solution to me, but on the other hand it compares to the perfectly legal way to show <code>UIImagePickerController</code> in a popover when pressing a button in a UIAlertController/action sheet (which itself is technically a popover, too).</p>
  
  <p>Any ideas are appreciated.</p>