   }
 
   func presentFired(timer: NSTimer) {
-    guard let userInfo = timer.userInfo,
+    guard let navigationController = self.navigationController,
+      userInfo = timer.userInfo,
       title = userInfo["title"] as? String,
       textColor = userInfo["textColor"] as? UIColor,
       backgroundColor = userInfo["backgroundColor"] as? UIColor,

  // MARK: - Animations

  func moveControllerViews(down: Bool) {
    guard let visibleController = navigationController.visibleViewController
      where Config.modifyInset
      else { return }


  }

  func silentWhisper(controller: UINavigationController, after: NSTimeInterval) {
    self.navigationController = controller
    guard let navigationController = self.navigationController else { return }
    
    var whisperSubview: WhisperView? = nil
    for subview in navigationController.navigationBar.subviews {
      if let whisper = subview as? WhisperView {
