Poptoviewcontroller

How to properly use popToViewController?

You can't instantiate a new instance of the view controller you are trying to pop to; you need to pop to the actual instance that is in the navigation stack.

If your menu is the root of your navigation stack then you can use popToRootViewController. If it is somewhere else in the stack then you either need to hold a reference to it or you can iterate through the navigation controller's viewControllers array to find it and then pop to it.

if let navController = self.navigationController {
    for controller in navController.viewControllers {
        if controller is MenuController { // Change to suit your menu view controller subclass
            navController.popToViewController(controller, animated:true)
            break
        }
    }
}

popTOViewController

Try this.

Where I have written SeeMyScoresViewController you should write your View Controller class on which you have to go.(eg. Class of Home)

NSArray *viewControllers = [[self navigationController] viewControllers];
for( int i=0;i<[viewControllers count];i++){
    id obj=[viewControllers objectAtIndex:i];
    if([obj isKindOfClass:[SeeMyScoresViewController class]]){
        [[self navigationController] popToViewController:obj animated:YES];
        return;
    }
}

popToViewController isn't popping all of the view controllers

Your confusion may simply be the way you are trying to "check" that the VCs are "popped".

Suppose you have gone:

root->TableView->A->B->A->B->B->B->`

At that point, the only VC that is visible is the last instance of A. So when you call

navController.popToViewController(controller, animated: true)

viewWillDisappear() will only be called on the last instance of A - none of the other VC instances will "disappear" because they are not visible.

If you want to confirm the other VCs in the stack are being "removed", put this in each view controller:

deinit() {
    print("I'm being removed:", self)
}

The other part of the question - do you want to animate through the process? So you would actually see the VCs "walk back up the stack"? If so, follow @FryAnEgg's link to Completion block for popViewController

Swift 3: popToViewController not working

popToViewController not work in a way you are trying you are passing a complete new reference of FirstTableViewController instead of the one that is in the navigation stack. So you need to loop through the navigationController?.viewControllers and find the FirstTableViewController and then call popToViewController with that instance of FirstTableViewController.

for vc in (self.navigationController?.viewControllers ?? []) {
    if vc is FirstTableViewController {
        _ = self.navigationController?.popToViewController(vc, animated: true)
        break
    }
}

If you want to move to First Screen then you probably looking for popToRootViewController instead of popToViewController.

_ = self.navigationController?.popToRootViewController(animated: true)

pass variable value by popToViewController in swift

Try this.

let viewControllers = self.navigationController!.viewControllers
  for var aViewController in viewControllers
  {
  if aViewController is LocationVC
     {
        let aVC = aViewController as! LocationVC
        aVC.NameofCircle = CName
        _ = self.navigationController?.popToViewController(aVC, animated: true)
     }
  }

another choice To pass value to Root ViewController

if let   myController  = self.navigationController?.viewControllers[0] as? LocationVC
  {
    myController.NameofCircle = CName
   _ =  self.navigationController?.popToViewController(myController, animated: true)
    }

popToViewController is not working but popViewController does

try this:-

for obj in (self.navigationController?.viewControllers)! {
    if obj is TestViewController {
        let vc2: TestViewController =  obj as! TestViewController
        vc2.data = data
        self.navigationController?.popToViewController(vc2, animated: true)
        break
    }
}

Make sure your view controller is added on navigationcontroller stack.

How to pass data when calling popToViewController?

For some reason the UIImageView on my 2nd UIViewController is not updating the image because I passed the UIImage in the dataPass model class. I changed the code like this :

func showSuccessPopUp() { // Based on DonMag's answer
    let popupVC = VehiclePhotoSuccessPopUpVC(nibName: "VehiclePhotoSuccessPopUpVC", bundle: nil)
    popupVC.modalPresentationStyle = .overCurrentContext
    popupVC.okTapped = { (sender) in
        // we want to find the Second VC in the stack, which will be [1]
        guard let destinationVC = self.navigationController?.viewControllers[1] as? RestructureFormVC else {
            fatalError("Second VC in navigation stack is NOT a RestructureFormVC")
        }

        destinationVC.source = "previewPhoto" // A string for knowing where the source is in the 2nd UIViewController
        destinationVC.assetPhoto = self.photoImage // Set the image immediately without using the dataPass model class
        self.navigationController?.popToViewController(destinationVC, animated: true)
    }

    self.present(popupVC, animated: false, completion: nil)
}

So here what I did was I just set the UIImage directly to the assetPhoto variable in my 2nd controller. And to update the UIImageView I create a function in my 2nd controller to check whether the assetPhoto variable is nil or not and call it in viewWillAppear like this:

override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        setAssetImage()
}

func setAssetImage() {
        if assetPhoto == nil {
            photoParentView.isHidden = true
        } else {
            photoParentView.isHidden = false
            photoImageView.image = assetPhoto
        }
}

And it works as I expected to be.

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