WKInterfaceTimer 用作定时器开始和停止倒计时

Question

我正在尝试创建一个计时器来倒计时 x 分钟和 y 秒。我正在计算秒数并像这样创建 InterfaceTimer： timer.setDate(NSDate(timeIntervalSinceNow:Double(secondsValue+1))) timer.stop()

之后我不停地停止它并一次又一次地启动它，但是值突然下降为 "time(now) doesn't stop"。例如：如果计时器显示：55，我启动它 3 秒然后停止它，它显示：52，我等待 10 秒然后再次启动它，它从 :42 开始。

我无法保存当前在WKInterfaceTimer 中的值，以便我可以从同一点重新开始。我尝试的一切都不起作用。有没有人使用计时器并且在停止后它保持相同的值？

Answer 1

是的，watchkit 计时器有点……笨拙……而且绝对不是很直观。但这只是我的意见

每次用户选择恢复计时器时，您都必须继续设置 date/timer。

请记住，您还需要一个内部 NSTimer 来跟踪事物，因为当前的 WatchKit 计时器只是用于显示而没有附加任何实际逻辑。

所以也许是这样的……不优雅。但它有效

     @IBOutlet weak var WKTimer: WKInterfaceTimer! //watchkit timer that the user will see

        var myTimer : NSTimer?  //internal timer to keep track 
        var isPaused = false //flag to determine if it is paused or not
        var elapsedTime : NSTimeInterval = 0.0 //time that has passed between pause/resume
        var startTime = NSDate()
        var duration : NSTimeInterval = 45.0 //arbitrary number. 45 seconds

       override func willActivate(){
           super.willActivate()
           myTimer = NSTimer.scheduledTimerWithTimeInterval(duration, target: self, selector: Selector("timerDone"), userInfo: nil, repeats: false)
           WKTimer.setDate(NSDate(timeIntervalSinceNow: duration ))
            WKTimer.start()
       }

    @IBAction func pauseResumePressed() {
        //timer is paused. so unpause it and resume countdown
        if isPaused{
            isPaused = false
            myTimer = NSTimer.scheduledTimerWithTimeInterval(duration - elapsedTime, target: self, selector: Selector("timerDone"), userInfo: nil, repeats: false)
            WKTimer.setDate(NSDate(timeIntervalSinceNow: duration - elapsedTime))
            WKTimer.start()
            startTime = NSDate()
            pauseResumeButton.setTitle("Pause")


          }
          //pause the timer
          else{
                isPaused = true

                //get how much time has passed before they paused it
                let paused = NSDate()
                elapsedTime += paused.timeIntervalSinceDate(startTime)

                //stop watchkit timer on the screen
                WKTimer.stop()

                //stop the ticking of the internal timer
                myTimer!.invalidate()

                //do whatever UI changes you need to
                pauseResumeButton.setTitle("Resume")
            }
        }

      func timerDone(){
           //timer done counting down
      }

WKInterfaceTimer 用作定时器开始和停止倒计时

WKInterfaceTimer used as a timer to countdown start and stop

nsdate

ios

swift

watchkit