NotificationCenter swift3无法观察帖子 [英] NotificationCenter swift3 Can't observe post

问题描述

我有3条通知:

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)

每个帖子我在视图控制器中都有一个不同的观察者

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

第一:NotificationCenter.default.addObserver(forName:NSNotification.Name("Notification1"), object: nil, queue: nil, using: updateUx)

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

第二:NotificationCenter.default.addObserver(forName:NSNotification.Name("Notification2"), object: nil, queue: nil, using: updateUx)

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

第三:NotificationCenter.default.addObserver(forName:NSNotification.Name("Notification3"), object: nil, queue: nil, using: updateUx)

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

updateUx函数仅包含通知的打印内容.

updateUx func contain only a print of notification.

我只收到第一条通知，我无法抓住另外两个，我也不知道为什么.

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

推荐答案

添加您的观察者，如下所示:

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)

你很好.

完整源代码(此项目在视图上具有UIButton，并且在情节提要中已连接@IBAction.点击该按钮时，将发布所有3条通知.日志应该在控制台中打印三次)

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...")
    }
}

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