NSNotification for all views at once

Question

I am trying to addObserver to all my views, when I start my application. When there is a post coming I want to display a Modal View on top of the current ViewController.

Is there a way to install it directly on every View or do I need to do the

viewWillAppear : add
viewDidDisappear : remove

workaround each time ?

You could make all your UIViewController inherits from a UIViewController that will add/remove the observing and even show the modal view. — Larme, Oct 07 '16 at 15:22

score 1 · Accepted Answer · answered Oct 07 '16 at 15:25

1

You could have created one superclass for all you view controllers and override viewWillAppear/viewDidDisappear there.
If there is no exception and you want to present a modal view controller no matter what view controller is currently on screen, you can present it over self.window.rootViewController in AppDelegate's didReceiveRemoteNotification method.

answered Oct 07 '16 at 15:25

alexburtnik

7,243
4
27
63

1

You can also swizzle `viewDidAppear:` and/or `viewWillDisappear:`. I'd probably use option 1 myself, but it is an option. – AdamPro13 Oct 07 '16 at 15:29

score 1 · Answer 2 · edited May 23 '17 at 10:34

1

Create parent class like this and subclass all other classes

import UIKit

class TemplateClassVC: UIViewController {


override func viewWillAppear() {
}

override func viewDidDisappear() {
}


}

and find top viewcontroller like this Get top most UIViewController

edited May 23 '17 at 10:34

Community

1
1

answered Oct 07 '16 at 18:10

neprocker

171
4

NSNotification for all views at once

2 Answers2