ios - swift:在零时停止倒数计时器

Question

我是 Swift 的新手 - 正在尝试为 iPhone/iPad 构建应用程序。希望你能帮我。

我想添加一个从 04:00 分钟倒计时到 00:00 的计时器。然后它应该停在零并触发声音效果(我还没有尝试实现)。当您按下开始按钮时，倒计时开始(在我的代码中，startTimer 和 stopTimer 指的是同一个按钮；但是，按钮在开始时只被按下一次)。

计时器开始倒计时。它按计划将秒数转换为分钟数。但是，我的主要问题是我无法让倒计时停在零。它继续超过 00:0-1 等。我该如何解决这个问题？

import Foundation
import UIKit
import AVFoundation


class Finale : UIViewController {



    @IBOutlet weak var timerLabel: UILabel!


    var timer = NSTimer()
    var count = 240
    var timerRunning = false




    override func viewDidLoad() {
        super.viewDidLoad()

    }



    func updateTime() {
        count--


        let seconds = count % 60
        let minutes = (count / 60) % 60
        let hours = count / 3600
        let strHours = hours > 9 ? String(hours) : "0" + String(hours)
        let strMinutes = minutes > 9 ? String(minutes) : "0" + String(minutes)
        let strSeconds = seconds > 9 ? String(seconds) : "0" + String(seconds)
        if hours > 0 {
            timerLabel.text = "\(strHours):\(strMinutes):\(strSeconds)"
        }

        else {
            timerLabel.text = "\(strMinutes):\(strSeconds)"
        }

    }



    @IBAction func startTimer(sender: AnyObject) {

        var timer = NSTimer.scheduledTimerWithTimeInterval(1.0, target: self, selector: Selector("updateTime"), userInfo: nil, repeats: true)

    }

 func stopTimer() {

    if count == 0 {
        timer.invalidate()
        timerRunning = false
           }
    }



    @IBAction func stopTimer(sender: AnyObject) {
        timerRunning = false
     if count == 0 {
    timer = NSTimer.scheduledTimerWithTimeInterval(1.0, target: self, selector: Selector("stopTimer"), userInfo: nil, repeats: true)
        timerRunning = true
        }}

}

Answer 1

func updateTime() {
        count--


        let seconds = count % 60
        let minutes = (count / 60) % 60
        let hours = count / 3600
        let strHours = hours > 9 ? String(hours) : "0" + String(hours)
        let strMinutes = minutes > 9 ? String(minutes) : "0" + String(minutes)
        let strSeconds = seconds > 9 ? String(seconds) : "0" + String(seconds)
        if hours > 0 {
            timerLabel.text = "\(strHours):\(strMinutes):\(strSeconds)"
        }

        else {
            timerLabel.text = "\(strMinutes):\(strSeconds)"
        }
    stopTimer()
}