从Swift中的功能使计时器失效 [英] Invalidate Timer from Function in Swift

问题描述

我有一个用 Swift 编写的应用程序，并且在 viewDidLoad 中声明了 NSTimer ；计时器每秒运行一次功能.

I have an app written in Swift with an NSTimer declared in the viewDidLoad; the timer runs a function once every second.

这是我的 viewDidLoad()中的代码:

let checkStateTimer = NSTimer.scheduledTimerWithTimeInterval(1.0, target: self, selector: "callCheckState:", userInfo: nil, repeats: true)

当前，我有另一个函数要暂停定时器.我认为应该使用:

Currently, I have another function which is called which I want to pause the timer. It should, I believe, use:

checkStateTimer.invalidate()

但是，由于计时器位于 viewDidLoad 中，而不是函数中，或者未在函数中声明过，因此该函数无法访问 checkStateTimer .

However, because the timer is in the viewDidLoad and not the function or declared earlier, the function cannot access the checkStateTimer.

麻烦的是，我无法在 viewDidLoad 之外(即仅在类中)声明计时器，因为它会导致错误.

Trouble is, that I can't declare the timer outside the viewDidLoad (i.e just in the class) because it results in an error.

所以，我的问题是，如何获取视图，以便它将在 viewDidLoad 上启动计时器，但是能够在函数运行时暂停计时器.如何做到这一点的最佳方法，以便它可以停止计时器?

So, my question is, how do I get the view so that it will start the timer on viewDidLoad, but be able to pause the timer when the function runs. How is the best way of doing this so that it can stop the timer?

推荐答案

将您的计时器声明为类变量:

Declare your timer as a class variable:

var checkStateTimer: NSTimer!

然后在viewDidLoad()中进行设置:

And then set it in viewDidLoad():

func viewDidLoad() {
    super.viewDidLoad()
    checkStateTimer = NSTimer.scheduledTimerWithTimeInterval(1.0, target: self, selector: "callCheckState:", userInfo: nil, repeats: true)
}

然后您的函数中的计时器无效:

Then in your function invalidate the timer:

func someFunction() {
    checkStateTimer.invalidate()
}

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