Dismiss view controller when navigating

Question

I'm creating an IOS Application in swift and I found a pretty big problem in my case.

If I would do this in Android I would use fragments and just replace the current fragment to a new one, but nothing seem to be equal to fragment in swift, so.

I start on view controller A and then I'm navigating to view controller B (The user should just pick their name in this view) and from B I want to navigate to C. But when I navigate to C I need view controller B to be dismissed to avoid the stacking. But I can't find a good way to just remove the current view controller and navigate to a new one.

    func navigateToService(selectedCar: String!){

    if let storyboard = storyboard{
        let vc = storyboard.instantiateViewController(withIdentifier: "BookServiceViewController") as! BookServiceViewController

        self.dismiss(animated: true) //<---

        vc.selectedCar = selectedCar

        self.present(vc, animated: true)
    }
}

I've tried this and a lot more so far. But nothing seem to work in my case. The code I've added in the thread is just closing the view immediately and is not opening a new one.

So how can I navigate from A -> B -> Dimiss B -> C?

TEMPORARY EDIT, WILL BE REMOVED

    func navigateToService(selectedCar: String!){

    self.dismiss(animated: true) {
        if let storyboard = self.storyboard{
           let vc = storyboard.instantiateViewController(withIdentifier: "BookServiceViewController") as! BookServiceViewController


           vc.selectedCar = selectedCar

           self.present(vc, animated: true)
       }
    }

}

if you want to go back from C to A, you can use unwindSegue via storyboard, or popToViewController(viewControllerA). There is no need to dismiss B — Alexandr Kolesnik, Dec 05 '19 at 10:19
@AlexandrKolesnik The reason why I want to dismiss B is because I'm using "automatic" and when I drag view controller C (to make it dismiss) the view controller B is still there. So I've to dismiss both C and B when dragging down to dismiss — Putte, Dec 05 '19 at 10:20
Have you tried `self.present(vc, animated: true, completion: { self.dismiss(animated: true) })`? — Linh Quang Pham, Dec 05 '19 at 10:21
in this case you must pass selected item from B to A, dismiss B in completionBlock, call C — Alexandr Kolesnik, Dec 05 '19 at 10:21
you can try to add your first vc as a subview and then remove it from parent and set your next view — Wassim Ben Hssen, Dec 05 '19 at 10:28
This could probably help you [Dismiss view controller](https://stackoverflow.com/questions/24668818/how-to-dismiss-viewcontroller-in-swift) — Zak, Dec 05 '19 at 10:51
@AlexandrKolesnik what do you mean with selected item? The name in vc B? — Putte, Dec 05 '19 at 10:54
@Was'SiimBenHssen Subview is like a container? or what is a subview in this case? — Putte, Dec 05 '19 at 10:54
@Putte yes its like a container check this maybe it will helps https://stackoverflow.com/questions/30932428/loading-a-view-controller-inside-a-view-in-xcode — Wassim Ben Hssen, Dec 05 '19 at 11:01

eemrah · Answer 1 · 2019-12-05T10:42:57.067

0

self.dismiss(animated: true) {
   # do your job in here
}

present your UIViewController in here but you have to get an instance of the UIViewController which will be presented.

Edit

Describe a protocol

protocol Handler{
    func  handleIt()
}


class AController: UIViewController, Handler {

    func handleIt() {
        // present controller C
        /*
         self.present( C Controller )
         */
    }
...

    func presentFunction(){

        var controller = BController()
        controller.delegate = self

    }

}

Conformance it with this protocol then set it with the present C controller.

class BController: UIViewController{

    var delegate: Handler?

    func dismissFunction(){

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

        delegate?.handleIt()

    }
    ...
}

In controller B you have to describe like this. So when you trigger dismiss function call the delegate's handleIt function. It presents C from A.

I hope it helps you.

edited Dec 05 '19 at 10:42

answered Dec 05 '19 at 10:22

eemrah

1,603
3
19
37

Check my temporary edit, please. :) Thats how you mean? – Putte Dec 05 '19 at 10:25
yeah, can you try it basically? – eemrah Dec 05 '19 at 10:26
I tried. But it closes both view controller B & C :/ – Putte Dec 05 '19 at 10:27
Actually the working scheme is true because you are present B from A, your base `UIViewController` is `A`. – eemrah Dec 05 '19 at 10:31
True. My base vc is A (also the root), and then I want to temporary show vc B (just to pick the correct name) and once I press navigate to C, I would like to get vc B to disappear. I hope you understand, I don't know how to explain it good enough. – Putte Dec 05 '19 at 10:32
I edited it to work as you wish. You better use protocol based solution. – eemrah Dec 05 '19 at 10:39
I'm a bit confused.. Where should I add all this? Haha – Putte Dec 05 '19 at 10:41
I'll try and see what I can do. But doesn't this seem to be a very "hard" way of doing this? I mean, why don't they just have an easy shit like "dismiss(animated: false){ self.present(vc, animated: true)}" – Putte Dec 05 '19 at 10:44
Because you'll call dismiss function in B, so that means B will die. Then you try to present C from not A but B so dead one :) – eemrah Dec 05 '19 at 10:45
Makes a bit sense hehe. But, inside your "handle" it function, you have commented out code. Should I leave it like that? or should I add code for navigating to C? – Putte Dec 05 '19 at 10:48
you have to code for self.present( CViewController ) – eemrah Dec 05 '19 at 11:18

Sagar Sangani · Answer 2 · 2019-12-06T12:19:04.910

0

Try this code:-

First, your current presented view(B) make push view with this code and after try to present your 'BookServiceViewController' view(C)

    let nextVC = self.storyboard?.instantiateViewController(withIdentifier: "Your_Current_Presented_View") as! Your_Current_Presented_View

    let nav = UINavigationController(rootViewController: nextVC)
    nav.navigationBar.isHidden = true
    DispatchQueue.main.async {
        self.present(nav, animated: true, completion: nil)
    }

And after present, Call your function

func navigateToService(selectedCar: String!){

if let storyboard = storyboard{
    let vc = storyboard.instantiateViewController(withIdentifier: "BookServiceViewController") as! BookServiceViewController

    self.dismiss(animated: true) //<---

    vc.selectedCar = selectedCar

    self.present(vc, animated: true)
}}

edited Dec 06 '19 at 12:19

answered Dec 05 '19 at 10:25

Sagar Sangani

287
2
7

It's closing both B and C :/ – Putte Dec 05 '19 at 10:27
@Putte I edit my answer because it not works. try my new code please, i'm edit now. remind it's all change. – Sagar Sangani Dec 06 '19 at 12:13
I edit my answer, if not understand tell me your confusion. – Sagar Sangani Dec 06 '19 at 12:21

score 0 · Answer 3 · answered Dec 05 '19 at 11:04

In A:

func goToB(_ sender: Any) {
        guard let controller = self.storyboard?.instantiateViewController(withIdentifier: "B_ViewController") as? B_ViewController else{return}
        self.present(controller, animated: true, completion: nil)
    }

func proceedToC(selectedCar:String){
        guard let controller = self.storyboard?.instantiateViewController(withIdentifier: "C_ViewController") as? C_ViewController else{return}
        controller.car = selectedCar
        self.present(controller, animated: true, completion: nil)
}

In B:

func goToC(_ sender: Any) {
        if let presenter = self.presentingViewController, presenter.isKind(of: A_ViewController.self), let vc = presenter as? A_ViewController{
            self.dismiss(animated: false) {
                vc.proceedToC(selectedCar: "Corvette")
            }
        }

This is one way to do it. However, I'd suggest using @elia's way as it is more elegant approach — The Pedestrian, Dec 05 '19 at 11:11
I did try, but didn't work really. I changed a bit on the application and I'm running this is another way atm. But I'll see if I will give it another try soon. :) Thanks — Putte, Dec 06 '19 at 16:53

Manish · Answer 4 · 2019-12-05T12:15:38.193

0

1.when you are navigating to B just pass the A controller object like this:- @IBAction func GoToB(_ sender: Any) { let Bcontroller = self.storyboard?.instantiateViewController(withIdentifier: "B") as! B Bcontroller.Aobje = self self.navigationController?.pushViewController(Bcontroller, animated: true) }

2.the time of navigation from B to C use A controller object for navigation like given below.

var Aobje = A()

override func viewDidLoad() {
    super.viewDidLoad()
}

@IBAction func BtoC(_ sender: Any) {
    let Ccontroller = self.storyboard?.instantiateViewController(withIdentifier: "C") as! C
         Aobje.navigationController?.pushViewController(Ccontroller, animated: true)
    self.removeFromParent()
}

edited Dec 05 '19 at 12:15

answered Dec 05 '19 at 11:50

Manish

1
1

Can you be more specific? :) – Putte Dec 05 '19 at 11:50
I don't fully understand what you mean – Putte Dec 05 '19 at 11:52
1. create a A controller type object in B controller. – Manish Dec 05 '19 at 11:53
Like how can I do that? :o – Putte Dec 05 '19 at 11:53
i have changed the post with the code so use it. – Manish Dec 05 '19 at 12:20

score 0 · Answer 5 · edited Jun 20 '20 at 09:12

Multiple dismissal at same time

You should dismiss the controller who presents this one to dismiss both together in this case:

self.presentingViewController!.dismiss(animated: true) // `!` is to makeing sure it's not crashing.

Demo:

Use this simple code to demo:

class ViewController: UIViewController {
    @IBAction func present() {
        let destination = storyboard!.instantiateInitialViewController()!
        if presentingViewController != nil {
            // You are not in the A
            if presentingViewController?.presentingViewController != nil {
                // You are in the C
                presentingViewController?.presentingViewController?.dismiss(animated: true)
                return
            } else {
                // You are in the B
                destination.modalPresentationStyle = .currentContext
            }
        }
        present(destination, animated: true, completion: nil)
    }
}

Usage:

Create a single view application
Drag a button into the view controller
Replace the ViewController class with the provided code
Connect the @IBAction
Run it to see the result.

Change the root of the window entirely:

If you want to get rid of the entire stack and act like you just start the app starting from the C view controller, you can just set the root of the window to C.

view.window!.rootViewController = destination

This is like you set the initialViewController arrow on the destination at first place.