title: NSNotification will not dismiss modal view
body: <p><strong>Task:</strong>
  I have a navigation controller that pushes a modalview, called login.  This login view has a button that pushes another modalview, called signup. If a user signs up the the signup modal AND the login modal should dismiss.  I have created an nsnotification within the login view that waits for a post from the signup submission action. </p>
  
  <p><strong>Problem</strong> The login receives the notification, but does not dismiss the login view. I know that the method runs, because an NSLog fires.</p>
  
  <p>Login viewDidLoad</p>
  
  <pre><code>[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(dismiss) name@"SignedUp" object nil];
  </code></pre>
  
  <p>Login dismiss</p>
  
  <pre><code>NSLog(@"Dismiss"); // this fires
  [self dismissModalViewControllerAnimated: YES];
  </code></pre>
  
  <p>Signup method (Child Controller)</p>
  
  <pre><code>[self dismissModalViewControllerAnimated: YES];
  [[NSNotificationCenter defaultCenter] postNotificationName:@"SignedUp" object:[self parentViewController]];
  </code></pre>
  
  <p>I have also tried this after calling dismiss in the signup method</p>
  
  <pre><code>[self.parentViewController dismissModalViewControllerAnimated:YES];
  </code></pre>
  
  <p><strong>Edit</strong> I'm not pushing these controllers. I am using <code>presentModalViewController</code></p>