ios - 我的计时器没有重置也没有停止

Question

我想制作秒表。单击开始按钮我的计时器是开始按钮单击停止我的计时器不会停止。单击重置我的计时器重置然后重新开始是不正确的行为。请帮忙。我是 swift 的新手。任何帮助将不胜感激。提前致谢

 class ViewController: UIViewController {
        @IBOutlet var label:UILabel?
        var time: Int!
        var appTimer :NSTimer = NSTimer()
        override func viewDidLoad() {
            super.viewDidLoad()
           time = 0
            label?.text = self.getFormattedString()
            // Do any additional setup after loading the view.
        }

    }
    extension ViewController
    {
        func getFormattedString() ->NSString
        {

            var t :Int = time!
            var minQuotient :Int = time/600
            var  minRemainder:Int = time%600
            var secQuotient:Int = minRemainder/10
            var secRemainder:Int = minRemainder%10
            var  minString :NSString = NSString(format: "%d", minQuotient)
            var secString :NSString = NSString(format: "%d", secQuotient)
            if secQuotient < 10
            {
                secString = NSString(format: "0%@", secString)

            }
            var secRemainderString :NSString = NSString(format: "%d", secRemainder)
            return NSString(format: "%@:%@.%@",minString,secString,secRemainderString)



        }




        @IBAction func statrt()
        {
           appTimer.invalidate()
            var timer :NSTimer = NSTimer.scheduledTimerWithTimeInterval(0.1, target: self, selector:Selector("stopWatch:") , userInfo: nil, repeats: true)
        }

        func stopWatch (theTimer:NSTimer)
        {
            time = time+1
            var b : String = self.getFormattedString()
            label?.text = b
        }



        @IBAction func stop()
        {
             self.appTimer.invalidate()
        }


        @IBAction func reset()
        {
             self.appTimer.invalidate()
           time = 0
            label!.text = self.getFormattedString()
        }
    }

Answer 1

你的计时器实例变量应该是可选的，而不是初始化为一个无效的计时器实例:

var appTimer :NSTimer?

然后，当您创建新的计时器实例时，您需要将其存储到该实例变量中，而不是仅仅将其创建为函数中的局部变量:

appTimer = NSTimer.scheduledTimerWithTimeInterval(0.1, target: self, selector:Selector("stopWatch:") , userInfo: nil, repeats: true)

我还建议您尝试在使用 self. 时保持一致，这样您就知道自己在做什么与实例和本地状态管理相关。