Where to remove observer for NSNotification in Swift?

Question

Where should I remove the observer for NSNotification in Swift, since viewDidUnload and dealloc() are unavailable?

Answer 1

You can use three methods:

1. after popViewController, back navigationController or dismissViewControllerAnimated:

   deinit {
       print("Remove NotificationCenter Deinit")
       NSNotificationCenter.defaultCenter().removeObserver(self)
   }
   

2. viewDidDisappear, remove after it is already the next view controller:

   override func viewDidDisappear(animated: Bool) {
       NSNotificationCenter.defaultCenter().removeObserver(self)
   }
   

3. viewWillDisappear - before opening the next view:

   override func viewWillDisappear(animated: Bool) {
       NSNotificationCenter.defaultCenter().removeObserver(self)
   }
   

Swift 3.0 syntax:

NotificationCenter.default.removeObserver(self)