How to access my custom UIPresentationController from within presented controller?

Question

This is how I perform transitioning:

extension UIViewController: UIViewControllerTransitioningDelegate {

    public func presentationController(forPresented presented: UIViewController, presenting: UIViewController?, source: UIViewController) -> UIPresentationController? {
        return OverlayPresentationController(presentedViewController: presented, presenting: presenting)
    }

    func presentOverlayController(_ controller: UIViewController) {

        controller.modalPresentationStyle = .custom
        controller.transitioningDelegate = self

        present(controller, animated: true)
    }
}

And then within my presented controller (AlertVC) at some point I need to access its presentation controller:

print(presentationController as? OverlayPresentationController) //nil
print(presentationController) //is ok, UIPresentationController

Why?

Presenting:

let controller = AlertVC.instantiate()
controller.update()
presentOverlayController(controller)

class AlertVC: UIViewController {

    class func instantiate() -> AlertVC {
        return UIStoryboard(name: "Alert", bundle: Bundle(for: LoginVC.classForCoder())).instantiateInitialViewController() as! AlertVC
    }

    func update() {
        _ = view

        print(presentationController as? OverlayPresentationController) //nil
    }
}

UIPresentationController has a property named containerView. It holds the view hierarchy of the presentation and presented controllers — Prashant Tukadiya, Jul 26 '17 at 10:24
Sounds promising... is it possible to access my presentation controller this way? — Bartłomiej Semańczyk, Jul 26 '17 at 10:26
Sorry I don't know about that , I have read it over internet so i share it with you , you may try if works then your lot's of time will be saved . Good luck — Prashant Tukadiya, Jul 26 '17 at 11:19

score -3 · Answer 1 · answered Jul 26 '17 at 10:06

-3

You get the view controller that is presenting the current view controller by calling presentingViewController

// The view controller that presented this view controller (or its farthest ancestor.)
self.presentingViewController

If your presenting view controller is in a navigation controller that returns a UINavigationController. You can get the view controller you need like so:

let presentingNVC = self.presentingViewController as? UINavigationViewController
let neededVC = presentingNVC.viewControllers.last as? NeededViewController

answered Jul 26 '17 at 10:06

Casper Zandbergen

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@BartłomiejSemańczyk Where did you try to call `presentingViewController` ? If you try to call it in `viewDidLoad:` it is possible that the value is not set yet. – Casper Zandbergen Jul 26 '17 at 10:13
@BartłomiejSemańczyk and are you sure you are calling it in the view controller that you present using `present(controller, animated: true)`? – Casper Zandbergen Jul 26 '17 at 10:16
@BartłomiejSemańczyk I think you are missing `presentationController.delegate = self` above the return statement in `presentationController(forPresented:presenting:source:)` – Casper Zandbergen Jul 26 '17 at 10:33
@BartłomiejSemańczyk Can you add your init code to the question? – Casper Zandbergen Jul 26 '17 at 10:40

How to access my custom UIPresentationController from within presented controller?

1 Answers1