Question

我正在创建一个应用程序，其中文本字段输入在标签上显示另一个文本字段上指示的时间量（以秒为单位）。我的应用程序仅在var seconds设置为整数而不是文本字段输入时运行。当我将var seconds设置为文本字段输入时，我在指定的代码行中收到以下错误：'ViewController' does not have a member named 'seconds'任何人都可以提供帮助吗？感谢。

以下是我的所有代码，错误代码行旁边有//Error：

class ViewController: UIViewController {


@IBOutlet weak var chronometre: UILabel!
@IBOutlet weak var prochainpointLabel: UILabel!
@IBOutlet weak var pointactuelLabel: UILabel!
@IBOutlet weak var point1Textfield: UITextField!
@IBOutlet weak var point1tempsTextfield: UITextField!
@IBOutlet weak var point2Textfield: UITextField!
@IBOutlet weak var point2tempsTextfield: UITextField!

var timer = NSTimer()
var seconds = point1tempsTextfield.text.toInt()

func subtractTime(dt:NSTimer){
        seconds-- //Error
        chronometre.text = "\(seconds)" //Error
    if(seconds == 0) { //Error
        seconds = point2tempsTextfield.text.toInt()
        pointactuelLabel.text = point2Textfield.text
        prochainpointLabel.text = nil

    }
}


override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}





@IBAction func presenterButton(sender: AnyObject) {
    pointactuelLabel.text = point1Textfield.text
    prochainpointLabel.text = point2Textfield.text
    chronometre.text = "\(seconds)" //Error
    timer = NSTimer.scheduledTimerWithTimeInterval(1.0, target: self, selector: ("subtractTime:"), userInfo: nil, repeats: true)
        }

}

感谢您的帮助，我对编码非常陌生，非常感谢！

Answer 1

忘记使用计时器来计算时间。您应该在两个日期之间使用NSTimeInterval来测量经过的时间。

ElapsedTime

extension NSTimeInterval {
    var time:String {
        return String(format:"%02d:%02d", Int((self/60.0)%60), Int((self) % 60 ))
    }
}


var startTime:NSTimeInterval = 0
var elapsedTime:NSTimeInterval = 0

startTime =  NSDate().timeIntervalSinceReferenceDate  // 446644854.4675

sleep(3)   //
elapsedTime = NSDate().timeIntervalSinceReferenceDate - startTime  // 3.005680024623871

println(elapsedTime.time) "00:03"

//将此概念应用于您的代码将如下所示：

class ViewController: UIViewController {
    @IBOutlet weak var chronometre: UILabel!
    @IBOutlet weak var prochainpointLabel: UILabel!
    @IBOutlet weak var pointactuelLabel: UILabel!
    @IBOutlet weak var point1Textfield: UITextField!
    @IBOutlet weak var point1tempsTextfield: UITextField!
    @IBOutlet weak var point2Textfield: UITextField!
    @IBOutlet weak var point2tempsTextfield: UITextField!

    var timer = NSTimer()
    var startTime:NSTimeInterval = 0

    func updateTime(){
        chronometre.text = (NSDate().timeIntervalSinceReferenceDate - startTime).time
    }
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    @IBAction func presenterButton(sender: AnyObject) {
        pointactuelLabel.text = point1Textfield.text
        prochainpointLabel.text = point2Textfield.text
        timer = NSTimer.scheduledTimerWithTimeInterval(1/10, target: self, selector: ("updateTime:"), userInfo: nil, repeats: true)
        startTime =  NSDate().timeIntervalSinceReferenceDate  

    }
}

错误 - ＆＃39; ViewController＆＃39;没有名为＆＃39;秒＆＃39;

1 个答案: