CODEWITHSUNDEEP
iosswiftuiviewcontrolleruistoryboard
AndrewSB
AndrewSB

Reputation: 146

Custom segue from app delegate

I'm trying to perform a segue from my AppDelegate. I know I can't actually perform a segue from the AppDelegate, since a segue is a transition from one scene to another, so I instantiate the two ViewControllers concerned in my AppDelegate 

let storyboard = UIStoryboard(name: "Main", bundle: nil)
let loadingViewController = storyboard.instantiateViewControllerWithIdentifier("loadingViewController") as UIViewController
let loginViewController = storyboard.instantiateViewControllerWithIdentifier("loginViewController") as UIViewController
let mainViewController = storyboard.instantiateViewControllerWithIdentifier("mainViewController") as UIViewController

Then later, I try to loadingViewController.performSegueWithIdentifier("segueToLogin", sender: self) where segueToLogin is a custom segue identifier in my storyboard

enter image description here

The error I get (which doesn't crash the app) is 

Tacklebox[27258:1016738] Warning: Attempt to present <Tacklebox.LoginViewController: 0x7fd8a9646bd0> on <Tacklebox.LoadingViewController: 0x7fd8a943d940> whose view is not in the window hierarchy!

and the end result is I stay on the sourceViewController, loadingViewController.

Upvotes: 1

Views: 1609

Answers (1)

Lyndsey Scott
Lyndsey Scott

Reputation: 37300

The problem is that you've created these view controllers in the App Delegate, but since you haven't used those particular instances to navigate between views, those view controller instances aren't the same view controllers actually on the stack; thus the error saying the LoadingViewController instance you're trying to segue to "is not in the window hierarchy."

You're going to have to get the instance of the active LoadingViewController. Since that view controller from which you're performing a segue is bound to be (i.e. supposed to be) visible and since (as indicated by your Storyboard), the rootViewController is a UINavigationController, try this to access the current LoadingViewController in the navigation hierarchy:

let navigationController = self.window?.rootViewController as UINavigationController
let loadingViewController = navigationController.visibleViewController as LoadingViewController
loadingViewController.performSegueWithIdentifier("segueToLogin", sender: self)

Upvotes: 3

Related Questions