NSTimer 失效不能正常工作

Question

我在我的项目中使用 NSTimer：

var clickTimer: Timer?

override func mouseDown(with event: NSEvent) {
    clickTimer = Timer.scheduledTimer(timeInterval: 2.0, target: self, selector: #selector(close(timer:)), userInfo: nil, repeats: false)
}

后来我在

中使它无效

override func mouseUp(with event: NSEvent) {
    if let timer = self.clickTimer {
        timer.invalidate()
    }
}

mouseUp里面的代码是运行但是定时器的close方法在2秒后还是运行。为什么失效不起作用？

Answer 1

您正在使 self.clickTimer 的实例无效，您应该使 self.clickTimer

无效

override func mouseUp(with event: NSEvent) {
  if let timer = self.clickTimer {
      self.clickTimer.invalidate()
  }
}

更新

我明白了，您没有启动 clickTimer！首先，如果你想这样做，你必须触发这个变量 -> clickTimer.fire()

然后当你想要时，你应该使它无效，

'Timer.scheduledTimer(timeInterval: 2.0, target: self, selector: #selector(close(timer:)), userInfo: nil, repeats: false)

当您想声明 clickTimer 但它不是您想要使其无效时自动运行！！！

Answer 2

尝试此代码，先使其无效，然后再删除引用。

override func mouseUp(with event: NSEvent) {
    self.clickTimer?.invalidate()
    self.clickTimer = nil
}

Answer 3

我现在明白了，您不想重新申报您的 clickTimer 所以您要做的是

if (self.clickTimer == nil) { 
    self.clickTimer = Timer.scheduledTimer(timeInterval: 2.0, target: self, selector: #selector(close(timer:)), userInfo: nil, repeats: false) 
}

只是想一想，您正在多次重新初始化 clicktimer，前一个已成功失效但您不小心重新声明了一个新计时器.. 嗯..

为了安全起见，我还建议您在 timer.invalidate() 之后添加 self.clickTimer = nil

Answer 4

当多次调用mouseDown(with:)时出现问题，您原来的计时器将被替换，因此您没有参考使其无效。

var clickTimer: Timer?

override func mouseDown(with event: NSEvent) {
    clickTimer?.invalidate()
    clickTimer = Timer.scheduledTimer(timeInterval: 2.0, target: self, selector: #selector(close(timer:)), userInfo: nil, repeats: false)
}

override func mouseUp(with event: NSEvent) {
    clickTimer?.invalidate()
}

Answer 5

试试这个

private var clickTimer: NSTimer?

func functionname() {
        guard clickTimer == nil else { return }
        clickTimer = NSTimer.scheduledTimerWithTimeInterval(15, target: self, selector: "fetchWallPosts", userInfo: nil, repeats: true)
    }

或

self. clickTimer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: (#selector(yourmethod)), userInfo: nil, repeats: true)

Answer 6

试试这个 -

if (self.clickTimer == nil) { 
self.clickTimer = Timer.scheduledTimer(timeInterval: 2.0, target: self, selector: #selector(close(timer:)), userInfo: nil, repeats: false) 
}

NSTimer 失效不能正常工作

NSTimer invalidation does not work properly

swift

macos

nstimer

更新