7

I have a container view which performs a couple of segues inside based upon a users actions. I also have a top UIView that I would like to control from within the container view segue and set it's state.

I've tried to set a delegate to the home controller using a protocol and also the following approach:

 if let parent = self.parent as? HomeController { 
        parent.handleTopBarState(state: .web)
 }

What I would like to happen is when I'm on a specific view controller, set the parent view controller's top bar view's state.

Thanks.

user7684436
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  • you can check this link...might be it will help you....http://stackoverflow.com/questions/8932313/how-can-i-access-a-parent-view-controllers-view-from-a-child-view-controller – prasad Mar 10 '17 at 12:43

2 Answers2

6

If you have added child view controller then you can access simply with self.parent. To make sure put it in if let and cast 

if let parent = self.parent as? ParentViewController {
        parent.resetItemsCollectionView()
    }
Ammar Mujeeb
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4

If you have embedded view controller on another view controller, you can message it's parent view controller with many ways.

  1. In child (embedded) view controller, you can have reference to parent. Give identifier to the embedding segue in the storyboard, declare var with type of the parent in child, and assign the parent on prepare(for segue: UIStoryboardSegue, sender: Any?) function, and call any public methods of the parent.
  2. Create protocol, make the parent confirm to the protocol, create var of the protocol in child, set parent as protocol object of the child in prepare(for segue: UIStoryboardSegue, sender: Any?), and call protocol methods whenever you want.
  3. Just post notification to NotificationCenter on child, and observe the notification on parent. Documentation of NotificationCenter, here you can find a brief example of using it.

Hope this helps!

PS: You can also observe properties of the child in the parent vc, if you want that way, I can explain.

Fahri Azimov
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  • I tried to access the parent using a protocol and this failed. How would the notification work? – user7684436 Mar 10 '17 at 13:03
  • If you want us the help with protocols, you should post the code where you are assigning the protocol object and where you are calling it. As for notifications, I will edit the answer to include more info about the `NotificationCenter` and notifications. – Fahri Azimov Mar 10 '17 at 13:05
  • Thanks, managed to get it working by passing data via notification userInfo. Is this the cleanest approach or would protocol be better? – user7684436 Mar 10 '17 at 13:40
  • Protocol would be better but you have to get a Ref to the controller. Notification is fine if that is the only thing that needs passed back. However this answer is correct and you should mark it correct. – agibson007 Mar 10 '17 at 14:55