Swift viewWillAppear not being called after dismissing view controller

29
votes

I am presenting a view controller from a view controller called HomeController like so:

let viewController = self.storyboard?.instantiateViewController(withIdentifier: "LoginController") as! LoginController

let navigationController: UINavigationController = UINavigationController(rootViewController: viewController)

present(navigationController, animated: true, completion: nil)

In the presented view controller LoginController at some point gets dismissed:

self.dismiss(animated: true, completion: nil)

But when it comes back to HomeController it is not calling viewWillAppear, I really need to check on condition on HomeController when it comes back to it, So how can I call viewWillAppear when LoginController dismisses the view?

3
iosswift
What is the presentation type on the controller? – Sulthan
Where would I set that or find out what type? It’s just a plain old present call – user979331
If the presentation is not over full screen or if the animation is custom, then the appearance methods are not called on the underlying controller. – Sulthan

3 Answers

38
votes

You need to set the correct presentationStyle. If you want that your presentedController will be fullScreen and call it the previous viewWillAppear, then you can use ".fullScreen" 

let viewController = self.storyboard?.instantiateViewController(withIdentifier: "LoginController") as! LoginController

let navigationController: UINavigationController = UINavigationController(rootViewController: viewController)

navigationController.modalPresentationStyle = .fullScreen

present(navigationController, animated: true, completion: nil)
4
votes

In iOS 13 , if you are presenting a view controller and when you are coming back viewWillAppear doesn't get called . I have changed it from present to push view controller and methods are getting called now .

0
votes

Changing presentation style to .fullScreen works but changes the appearance of the presented view Controller. If u want to avoid that u can override the viewWillDisappear method in the presented viewcontroller and inside it add presentingViewController?.viewWillAppear(true).

Example:

 class ViewControllerA: UIViewController {
 
      override func viewDidLoad() {
          super.viewDidLoad()
          
          //put the presenting action wherever you want

          let vc = ViewControllerB()
          navigationController.present(vc, animated: true)
      }

      override func viewWillAppear(_ animated: Bool) {
           super.viewWillAppear(animated) 
           //refresh Whatever 
      }
 }

 class ViewControllerB: UIViewController {
 
      override func viewDidLoad() {
          super.viewDidLoad()
      }

      override func viewWillDisappear(_ animated: Bool) {
          super.viewWillDisappear(animated)

          //this will call the viewWillAppear method from ViewControllerA  

          presentingViewController?.viewWillAppear(true)
      }
 }