How to dismiss 2 modal view controllers without weird animation

Question

I recreated the question and describe its essence more precisely.

I have two view controllers presented modally on Swift 4, without storyboard (can't use unwind) and without navigation controller

A presents B which presents C.

The reason why we don't use navigation controller, it's because we what simple animation from bottom to top and instead of breaking the standard animation from right to left, we decided to use present.

I would like to dismiss 2 view controllers and go from C to A.

Please, don't mark this question as duplicate before you read my question carefully. I found a tone of similar post, but neither solved my problem. Some of them Objective-C or some of the suggest to use:

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

Or:

self.presentingViewController?.dismiss(animated: false, completion: nil)
self.presentingViewController?.dismiss(animated: true, completion: nil)

It's works, but it create weird animation. It's just delete C and animate dismiss for B:

Expected result:

https://stackoverflow.com/a/37487975/ covers this problem; this is one of the answers to the first duplicate I provided yesterday. There's almost certainly more coverage of the problem in one of the many other duplicates. Please don't repost; edit [your previous question](https://stackoverflow.com/questions/54262992/how-to-dismiss-2-modal-view-controllers-without-weird-animation) instead. — jscs, Jan 19 '19 at 18:00

Robert Dresler · Answer 1 · 2019-01-19T12:13:07.253

Idea: you need to dismiss third controller with animation and after dismissing you need to dismiss second without animation. While third controller is being dismissed, second shouldn't be visible.

First, set Presentation style of second view controller to Over Current Context when you're presenting it (since we will need to hide its view when we will dismiss third controller)

let vc2 = VC2()
vc2.modalPresentationStyle = .overCurrentContext
present(vc2, animated: true)

continue with creating callbacks properties for willDismiss and didDismiss inside third controller. This callback will be called before and after you dismiss third controller

class VC3: UIViewController {

    var willDismiss: (() -> Void)?
    var didDismiss:  (() -> Void)?

    @IBAction func dismissButtonPressed(_ sender: UIButton) {

        willDismiss?()

        dismiss(animated: true) {
            self.didDismiss?()
        }
    }

}

then in second view controller in the place where you present third view controller, set third controller's callback properties: declare what happens when third controller will dismiss: you need to hide view of second and then after dismissing third you need to dismiss second without animation (view can stay hidden since view controller will be deinitialized)

class VC2: UIViewController {

    @objc func buttonPressed(_ sender: UIButton) {

        var vc3 = VC3()

        vc3.willDismiss = {
            self.view.isHidden = true
        }

        vc3.didDismiss = {
            self.dismiss(animated: false)
        }

        present(vc3, animated: true)
    }

}

Anyway, second option is using UINavigationController and then just call its method popToViewController(_:animated:).

André Slotta · Accepted Answer · 2019-01-19T17:52:46.800

1

Create a snapshot from the currently visible view and add it as a subview to the first presented view controller. To find that you can simply "loop through" the presenting view controllers and dismiss from the initial one:

@IBAction func dismissViewControllers(_ sender: UIButton) {
    var initialPresentingViewController = self.presentingViewController
    while let previousPresentingViewController = initialPresentingViewController?.presentingViewController {
        initialPresentingViewController = previousPresentingViewController
    }


    if let snapshot = view.snapshotView(afterScreenUpdates: true) {
        initialPresentingViewController?.presentedViewController?.view.addSubview(snapshot)
    }

    initialPresentingViewController?.dismiss(animated: true)
}

This is the result with slow animations enabled for the dismissal: https://www.dropbox.com/s/tjkthftuo9kqhsg/result.mov?dl=0

edited Jan 19 '19 at 17:52

answered Jan 19 '19 at 13:19

André Slotta

13,774
2
22
34

Hi André, with this solution is second controller visible while dismissing and this is the exact problem which OP has. You can check my answer if it gives you better view of the problem. – Robert Dresler Jan 19 '19 at 14:11
@RobertDresler You're right. Updated my answer. – André Slotta Jan 19 '19 at 17:47
Hi. Thank you for great solution, but how I can fix this for modalPresentationStyle = .overCurrentContext ? – Den Andreychuk Jan 21 '19 at 08:49
@DenAndreychuk Do you really need `.overCurrentContext`? In your example there is no need for it since the presented view controllers fully cover the view controllers underneath. – André Slotta Jan 21 '19 at 10:37
Yeap. We add gesture for swipe down dismiss and we need content for background – Den Andreychuk Jan 21 '19 at 11:06
Can you tell / show me what the current problem is? – André Slotta Jan 21 '19 at 11:08

score 0 · Answer 3 · answered Jan 19 '19 at 10:41

0

If you are not using a navigation controller and you want to dismiss all ViewControllers to show the root ViewController (assuming A is the root):

self.view.window?.rootViewController?.dismiss(animated: true, completion: nil)

answered Jan 19 '19 at 10:41

codeherk

1,609
15
24

Unfortunately A isn't root – Den Andreychuk Jan 19 '19 at 10:45

score 0 · Answer 4 · answered Jan 19 '19 at 10:42

0

Use this in button action method. The current VC will dismiss when you dismiss the parent VC. This will dismiss both VCs in single animation.

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

answered Jan 19 '19 at 10:42

Raghav Ahuja

66
6

How to dismiss 2 modal view controllers without weird animation

4 Answers4