所有呈现的视图控制器都不会被解雇

Question

I have a firstViewController that I display with

[self.navigationController pushViewController:firstViewController animated:true];

Then when a button in this first VC is clicked, I present a second one:

[self presentViewController:secondViewController animated:true completion:nil];

And from this second one I present the third VC as a modal:

[thirdVC modalPresentationStyle];
[thirdVC setModalPresentationStyle:UIModalPresentationOverCurrentContext];    
[self presentViewController:thirdVC animated:true completion:nil];

The problem is that I want to display the firstVC when the validate button of the last VC is clicked. So I have to dismiss the third and the second one. I tried this in the validateAction (in the third VC):

[[self parentViewController] dismissViewControllerAnimated:true completion:nil];
[self dismissViewControllerAnimated:true completion:nil];

But the result is that the thirdVC (the modal one) is dismissed, and from the debugger I can see that the firstVC is covered by the secondVC.

How can I dismiss the second and the third VC at the same time in order to return to the first one? NOTE: I want to push the firstVC after the dismiss of the others because I have to reload the data (in the fristVC viewDidLoad)

Answer 1

From Apple's Documentation :

The presenting view controller is responsible for dismissing the view controller it presented. If you call this method on the presented view controller itself, UIKit asks the presenting view controller to handle the dismissal.

In other words, the third viewController asks the second viewController to dismiss its presented viewController, which is the third one. Then the third viewController tries to dismiss itself, causing UIKit to ask the second viewController to dismiss the third one once more.

You will have to go one layer up and ask the first viewController to dismiss its presented view controller.

It is good practice that the third viewController does not know anything about the presentation hierarchy. You can use delegation to tell the first viewController that the task is finished. An exit segue is a very nice alternative if you use storyboards.

You only have to call -dismissViewControllerAnimated:completion: once if you address the first viewController:

If you present several view controllers in succession, thus building a stack of presented view controllers, calling this method on a view controller lower in the stack dismisses its immediate child view controller and all view controllers above that child on the stack.