title: application:openURL not triggered
body: <p>I have a problem implementing - (BOOL)application:openURL and using UIDocumentInteractionController for exporting PDF file from an application to another.</p>
  
  <p>(1) Target application does nothing but just display URL of the imported PDF file (in a label).</p>
  
  <p>here is the code in AppDelegate.m:</p>
  
  <pre><code>- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions: (NSDictionary *)launchOptions
  {
      self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
      self.viewController = [[ViewController alloc] initWithText:@"No file is imported."];
      self.window.rootViewController = self.viewController;
      [self.window makeKeyAndVisible];
  
      return YES;
  }
  
  - (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:   (NSString *)sourceApplication annotation:(id)annotation
  {
      if (url != nil)
      {
          [self.viewController handleOpenURL:url];
          return YES;
      }
      else
      {
          [self.viewController handleOpenURL:[NSURL fileURLWithPath:@"AppDelegate.h"]];
          return NO;
      }
  }
  </code></pre>
  
  <p>Method "handleOpenURL" just take the url and put in a label in the view controller and show an alert:</p>
  
  <pre><code>- (void)handleOpenURL:(NSURL *)fileURL
  {
      _text = [fileURL absoluteString];
      self.lblText.text = _text;
  
      UIAlertView * alert = [[UIAlertView alloc] initWithTitle:@"Alert" message:_text delegate:self cancelButtonTitle:nil otherButtonTitles:nil, nil];
      [alert show];
  }
  </code></pre>
  
  <p>(2) In source application, I simply use UIDocumentInteractionController to list "Open In" options (my target application appears well in the list)</p>
  
  <p>Here is the code:</p>
  
  <pre><code>_docInteractionController = [UIDocumentInteractionController interactionControllerWithURL:[NSURL fileURLWithPath:attachmentFile]];
  _docInteractionController.delegate = self;
  _docInteractionController.UTI = [_extensionUTIs objectForKey:[[attachmentFile pathExtension] lowercaseString]];
  BOOL opened = [_docInteractionController presentOpenInMenuFromRect:CGRectZero inView:self.view animated:NO];
  </code></pre>
  
  <p>(3) Problem:
  - When I select the target application (from "Open In" list), simulator switches from source application to target application okay, but looks like application:openURL method is not invoked because the label keeps as initial (No file is imported.) and no alert view shows up.</p>
  
  <p>Please advise me what could be wrong here ?</p>
  
  <p>Thanks in advance.</p>