title: iOS 8 How to use document provider extension with navigation controller?
body: <p>How i can put document provider extension in navigation controller to use the push and pop methods? iCloud document provider use it so I think it is possible, but when i embed document provider controller in navigation controller I receive an exception. When I pick my document provider i receive alert message on the screen "Failed to launch 'docProvider'", "The document picker 'docProvider' failed to launch(4097)."</p>
  
  <pre><code>    17545849:_UIScreenEdgePanRecognizerEdgeSettings.edgeRegionSize=13.000000
  2014-08-25 10:43:16.948 documentProvider[1851:423858] &lt;NSXPCConnection: 0x15526e50&gt; connection from pid 1849: Warning: Exception caught during decoding of received message, dropping incoming message.
  Exception: Exception while decoding argument 0 (#2 of invocation):
  &lt;NSInvocation: 0x1554f0d0&gt;
  return value: {v} void
  target: {@} 0x0
  selector: {:} __connectToViewControllerFromRemoteViewController:replyHandler:
  argument 2: {@} 0x0
  argument 3: {@?} 0x0 (block)
  
  Exception: value for key '&lt;no key&gt;' was of unexpected class '_NSXPCDistantObject'. Allowed classes are '{(
      NSNumber,
      NSNull,
      NSString,
      NSData,
      NSDate,
      NSDictionary,
      NSArray
  )}'.
  </code></pre>