Swift中的NSNotifications 3 [英] NSNotifications in Swift 3

问题描述

新通知目前是否在Swift 3中无效？我正在做：

Are the new notifications not currently working in Swift 3? I am doing:

NotificationCenter.default().post(name: DidTouchParticleView, 
                                  object: self.particle as? AnyObject)

在自定义视图的touchesBegan（）中我需要发送 particle 视图控制器的对象（如果有）。所以我这样做：

in a custom view's touchesBegan() and I need to send the particle object to the view controller if there is one. So I do this:

NotificationCenter.default().addObserver(forName: DidTouchParticleView, 
                                         object: self,
                                         queue: OperationQueue.main(),
                                         using: presentParticleDisplayView(notification:))

在视图控制器的viewDidLoad（）中。我确定当我点击我的自定义视图时，会显示该特定视图控制器，但是，从不调用函数 presentParticleDisplayView（notification :) 。

in a view controller's viewDidLoad(). I am certain that that particular view controller is the one presented when I tap my custom view, however, the function presentParticleDisplayView(notification:) is never called.

此外， DidTouchParticleView 在全球范围内定义如下：

Also, DidTouchParticleView is defined globally like this:

let DidTouchParticleView = NSNotification.Name("didTouchParticleView")

这是由于测试版，或者我做错了什么？

Is this due to the beta, or am I doing something wrong?

推荐答案

听起来你可能打算打电话给 addObserver（_：selector：name：object：），其中第二个参数消息（选择器：）被发送到第一个参数（目标）。

It sounds like you may be intending to call addObserver(_:selector:name:object:), where the second parameter message (the selector:) is sent to the first parameter (the target).

相反，你正在调用错误的方法， addObserver（forName：object：queue：using :) ，效果完全不同。

Instead, you are calling the wrong method, addObserver(forName:object:queue:using:), which works quite differently.

此外，关于问题的第二部分：

Also, as to the second part of your question:

let DidTouchParticleView = NSNotification.Name("didTouchParticleView")

这是正确的（差不多）;它应该是

That is correct (almost); it should be

let DidTouchParticleView = Notification.Name("didTouchParticleView")

所有通知名称现在都是 Notification.Name 个实例。这样做的正确方法是：

All notification names are now Notification.Name instances. The proper way to do this is to say:

extension Notification.Name {
    static let didTouchParticleView = Notification.Name("didTouchParticleView")
}

然后，您可以将通知的名称称为<$你的代码中有c $ c> .didTouchParticleView 。

You can then refer to the notification's name as .didTouchParticleView throughout your code.

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