NotificationCenter swift3 Can't observe post

Question

I have 3 notifications:

NotificationCenter.default.post(name:NSNotification.Name("Notification1"), object: nil)
NotificationCenter.default.post(name:NSNotification.Name("Notification2"), object: nil)
NotificationCenter.default.post(name:NSNotification.Name("Notification3"), object: nil)

And I have for each post one differents observer in view controller

First:NotificationCenter.default.addObserver(forName:NSNotification.Name("Notification1"), object: nil, queue: nil, using: updateUx)

Second:NotificationCenter.default.addObserver(forName:NSNotification.Name("Notification2"), object: nil, queue: nil, using: updateUx)

Third:NotificationCenter.default.addObserver(forName:NSNotification.Name("Notification3"), object: nil, queue: nil, using: updateUx)

updateUx func contain only a print of notification.

I only got my first notification I cannot catch the two other, I don't know why.

There's no way your first notification can be received. You are not observing to `Notification1`, but you are observing `DashboardNotification ` — viral, Feb 24 '17 at 10:54
are you sure the names are to add observer and post observer are same ? — Priyal, Feb 24 '17 at 10:56
Try changing `NotificationCenter.default.addObserver` like following. It should work. I tried it and it does. — viral, Feb 24 '17 at 11:01
Sorry my bad, for posting this on github, I change the name, I edit my question. — Badr Filali, Feb 24 '17 at 11:01
I am not facing any issue while using this code. Are you sure your observers are added and then notification is posted ? — Priyal, Feb 24 '17 at 11:06
Check updated answer. If this doesn't work, I don't know what would. :) — viral, Feb 24 '17 at 11:17
Where you remove observer? If you remove observer in viewWillDisappear, controller which currently not on screen will not receive any notification. — Bohdan Savych, Feb 24 '17 at 11:21

viral · Accepted Answer · 2017-02-24T11:15:38.153

Add your observers like following:

NotificationCenter.default.addObserver(self, selector: #selector(updateUx), name: NSNotification.Name("Notification1"), object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(updateUx), name: NSNotification.Name("Notification2"), object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(updateUx), name: NSNotification.Name("Notification3"), object: nil)

And you are good to go.

EDIT: Full source code (This project has a UIButton on view and the @IBAction is connected to it in storyboard. On tapping that button, all 3 notifications will get posted. The log is supposed to get printed thrice in console)

class ViewController: UIViewController {

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        NotificationCenter.default.addObserver(self, selector: #selector(updateUx), name: NSNotification.Name("Notification1"), object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(updateUx), name: NSNotification.Name("Notification2"), object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(updateUx), name: NSNotification.Name("Notification3"), object: nil)
    }

    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        NotificationCenter.default.removeObserver(self)
    }

    @IBAction func abc (_ sender: UIButton) {
        NotificationCenter.default.post(name:NSNotification.Name("Notification1"), object: nil)
        NotificationCenter.default.post(name:NSNotification.Name("Notification2"), object: nil)
        NotificationCenter.default.post(name:NSNotification.Name("Notification3"), object: nil)
    }

    func updateUx(){
        print("received...")
    }
}

NotificationCenter swift3 Can't observe post

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