如何从 appdelegate xcode 11 swift 5 呈现视图 controller

Question

I have been searching all day on how to present a view controller from within the appdelegate. It appears that in xcode 11 the window property was moved to the scenedelegate which has been confusing me. I want to present a view controller from within the appdelegate from the didReceiveRemoteNotification function so when the user receives a notification it takes them to a separate view controller with information. I have tried to do:

self.window?.rootViewController?.present(LoginViewController(), animated: false, completion: nil)

within the appdelegate which used to work in a previous application of mine but it does not seem to work anymore. Any help would be much appreciated.

Answer 1

I was able to solve this issue by using shared windows to get the window from scenedelegate to present the view controller on.

UIApplication.shared.windows.first?.rootViewController?.present(vc, animated: false, completion: nil)

Answer 2

Best approach to present view controller through app delegate is without falling for hierarchy like below:

if let vc = UIStoryboard(name: "YOURSTORYBOARD", bundle: nil).instantiateViewController(withIdentifier: "YOURVIEWCONTROLLER") as? YOURVIEWCONTROLLER {
if let window = self.window, let rootViewController = window.rootViewController {
    var currentController = rootViewController
    while let presentController = currentController.presentedViewController {
        currentController = presentController
    }
       currentController.present(vc, animated: true, completion: nil)
   }
}