Pass data on dismiss to view controller outside of navigation controller?

Question

As shown in the picture above, I have two view controllers, one of which is within a navigation controller. When a button is pressed in controller A, controller B is presented through the navigation controller and is displayed modally. Is it possible for me to pass data from controller B back to controller A when the dismiss function is called on B?

Modal segue should be pointing from A to the navigation controller reading your description — Andrey Volobuev, Jan 19 '17 at 01:07

score 0 · Answer 1 · answered Jan 19 '17 at 00:39

0

You can use delegation pattern or callbacks to do this

answered Jan 19 '17 at 00:39

Andrey Volobuev

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I've tried both of those, but that would require me to present view controller B, not the navigation controller. Presenting B instead of the navigation controller doesn't work because I need to be able to present and dismiss the whole view controller, not just B. – AlecR Jan 19 '17 at 00:41
In that case the easiest way is to use an `unwind segue` – Andrey Volobuev Jan 19 '17 at 00:47
And you still can use the delegation, for example in A: `if let navigationController = segue.destination as? UINavigationController, let b = navigationController.viewControllers.first as? BViewController{ b.delegate = self }`. And calling delegate method with data before dismissing B – Andrey Volobuev Jan 19 '17 at 01:24

score 0 · Answer 2 · edited May 23 '17 at 12:01

0

If you are using storyboards and navigating using segues, then an unwind segue will do this for you. Here is a simple tutorial that should help:

https://www.andrewcbancroft.com/2015/12/18/working-with-unwind-segues-programmatically-in-swift/

This stack overflow answer has much more detailed and valuable information on this topic

Passing Data between View Controllers

edited May 23 '17 at 12:01

Community

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answered Jan 19 '17 at 03:52

Guillermo Alvarez

1,695
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score 0 · Answer 3 · answered Jan 19 '17 at 04:49

You can pass through NSNotificationCentre .

First you need to add Notification Observer and its selector in ViewControllerA as below :

[[NSNotificationCenter defaultCenter] addObserver:self
                                          selector:@selector(receiveTestNotification:) name:@"notificationName"
                                               object:nil];

-(void) receiveTestNotification:(NSNotification*)notification
{
  NSDictionary* userInfo = notification.userInfo;
  NSLog (@"%@",userInfo);
}

Now in ViewController B you need to post notification as below :

 NSDictionary* userInfo = your data ;
 NSNotificationCenter* nc = [NSNotificationCenter defaultCenter];
[nc postNotificationName:@"notificationName" object:self userInfo:userInfo];

Pass data on dismiss to view controller outside of navigation controller?

3 Answers3