Question

我用这个计时器打了一堵墙。

我试图创建这个计时器，当游戏开始时，它将开始计数。当角色死亡时，它会停止。我把它全部工作了，但我的问题是我不能让它重新开始下一轮。

这是我的代码。

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

override func didMoveToView(view: SKView) {
    let aSelector : Selector = "updateTime"
    timer = NSTimer.scheduledTimerWithTimeInterval(0.01, target: self, selector: aSelector, userInfo: nil, repeats: true)
    startTime = NSDate.timeIntervalSinceReferenceDate()

    scoreLabel.fontName = "Helvetica"
    scoreLabel.fontSize = 40
    scoreLabel.text = "0"
    scoreLabel.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMaxY(self.frame) - 90)
    scoreLabel.zPosition = 20

    self.addChild(scoreLabel)
}

func updateTime() {
    var currentTime = NSDate.timeIntervalSinceReferenceDate()
    var elapsedTime: NSTimeInterval = currentTime - startTime
    let minutes = UInt8(elapsedTime / 60.0)
    elapsedTime -= (NSTimeInterval(minutes) * 60)
    let seconds = UInt8(elapsedTime)
    elapsedTime -= NSTimeInterval(seconds)
    let fraction = UInt8(elapsedTime * 100)

    let strMinutes = minutes > 9 ? String(minutes): "0" + String(minutes)
    let strSeconds = seconds > 9 ? String(minutes): "0" + String(seconds)
    let strFraction = fraction > 9 ? String(fraction): "0" + String(fraction)

    scoreLabel.text = "\(strMinutes):\(strSeconds):\(strFraction)"
}

func didBeginContact(contact: SKPhysicsContact) {
    if (gameOver) == 0 {
        timer.invalidate()
        gameOver = 1
        movingObjects.speed = 0
        gameOverLabel.fontName = "Helvetica"
        gameOverLabel.fontSize = 40
        gameOverLabel.text = "Game over! press to restart."
        gameOverLabel.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame) )
        gameOverLabel.zPosition = 20
        labelHolder.addChild(gameOverLabel)
    }
}

override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
    if (gameOver == 0) {
          my methods......
    } else {
        scoreLabel.text = "00:00:00"
        gameOver = 0
    }
}

Answer 1

来自Apple Doc

invalidate()阻止接收器再次发射并请求将其从运行循环中移除。

如果必须再次启动计时器，则需要再次初始化计时器。您必须重新启动计时器。一旦失效，计时器对象将无法重复使用。

停止一次后，Swift计时器不会重启

1 个答案: