CODEWITHSUNDEEP
iosobjective-cuiviewcontrollerunwind-segue
iht
iht

Reputation: 692

Close own uiviewcontroller after segue to child uiviewcontroller ios?

I have three UIViewControllers (let's call them A, B and C) in a navigation controller. A can segue into either B or C. B can segue into C. When C closes, I want it to always return to A, i.e. it automatically closes B upon closing C, if opened from B.

Now, I tried using segue unwinding, so that when C closes, B's return method gets called to dismiss the destination controller:

- (IBAction)returnFromC:(UIStoryboardSegue*)segue
{
    [segue.destinationViewController dismissViewControllerAnimated:YES completion:nil];
}

I put a breakpoint in this method - it is called. I have verified that the destinationController is indeed B. However, I noticed when the break point hits, C is still visible. After playing from the break point, C does exit as expected, but B is still visible.

Any ideas? Many thanks in advance.

Upvotes: 0

Views: 376

Answers (2)

Islam
Islam

Reputation: 3734

dismissViewControllerAnimated:completion: is used to dismiss a Modal segue and has no effect for Push segues

As @matt suggested you could just remove B (the middle) view controller from self.navigationController.viewControllers and here's a sample code that you can put in B view controller:

- (void)viewDidDisappear:(BOOL)animated {
    [super viewDidDisappear:animated];

    // No need to process if the viewController is already being removed
    if (!self.isMovingFromParentViewController) {
        // Getting a mutable copy of the viewControllers (can't directly modify)
        NSMutableArray *temp = [self.navigationController.viewControllers mutableCopy];

        // Removing 'self' -> so A > B > C will become A > C
        [temp removeObject:self];

        // Setting the new array of viewControllers
        self.navigationController.viewControllers = [temp copy]; // getting an immutable copy
    }
}

P.S. You could use popViewControllerAnimated: instead of Unwind segue if you're not planning to send the data back.

Upvotes: 0

matt
matt

Reputation: 534885

When C closes, I want it to always return to A, i.e. it automatically closes B upon closing C, if opened from B

The simplest solution is: in C's viewDidAppear:, secretly remove B as a child of the navigation controller. In other words, you've got this:

A > B > C

Now you rearrange things so that you've got this:

A > C

Thus, the only thing to go back to from C is A.

It's easy to manipulate the navigation controller's set of children in this way. Just call setViewControllers:animated: (with a second argument of NO).

[But if I've understood your setup properly, another easy way would be to implement the unwind method in A and not B. Then do an unwind segue. We always unwind to the first view controller that contains the unwind method, so that would always be A.]

Upvotes: 3

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