ios - 如何在用户点击暂停按钮时立即停止 UISlider？

Question

我已经使用 MPMoviePlayerController 实现了自己的自定义视频播放器控件，但遇到了问题。

当视频正在播放且 slider 前进时，如果我点击暂停按钮， slider 会在停止前额外移动一秒。

如何确保当用户点击暂停时，UISlider 立即停止？

override func viewDidLoad()
{
    super.viewDidLoad()

    youtubeVideoPlayer.moviePlayer.controlStyle = MPMovieControlStyle.None

    isSliderTouched = false

    initUI()

    tapGesture = UITapGestureRecognizer(target: self, action: "handleSingleTap:")

    tapGesture2 = UITapGestureRecognizer(target: self, action: "handleSingleTap:")
}

override func viewDidAppear(animated: Bool)
{
    super.viewDidAppear(true)

    timer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: "updateSlider", userInfo: nil, repeats: true)

    playerSlider.addTarget(self, action: "sliderMoveStart", forControlEvents: .TouchDown)

    playerSlider.addTarget(self, action: "sliderMoving", forControlEvents: .TouchDragInside)

    playerSlider.addTarget(self, action: "sliderMoveEnd", forControlEvents: .TouchUpInside)

    centerButton.addTarget(self, action: "onClick:", forControlEvents: .TouchUpInside)

    playerSlider.addGestureRecognizer(tapGesture2)

    lastControlTime = CFAbsoluteTimeGetCurrent()
}

override func viewWillDisappear(animated: Bool)
{
    super.viewWillDisappear(true)   

    timer.invalidate()

    playerSlider.removeTarget(self, action: "sliderMoveStart", forControlEvents: .TouchDown)      

    playerSlider.removeTarget(self, action: "sliderMoving", forControlEvents: .TouchDragInside)

    playerSlider.removeTarget(self, action: "sliderMoveEnd", forControlEvents: .TouchUpInside)

    centerButton.removeTarget(self, action: "onClick:", forControlEvents: .TouchUpInside)

    playerSlider.removeGestureRecognizer(tapGesture2)
}

func initUI()
{
    bottomBarBG = UIView(frame: CGRectMake(0, UIScreen.mainScreen().bounds.height - 75, UIScreen.mainScreen().bounds.width, 80) )

    playerSlider = UISlider()

    playerSlider.setThumbImage(UIImage(named: "slider"), forState: .Normal)

    playerSlider.continuous = true

    playerSlider.highlighted = true

    playerSlider.frame = CGRectMake(UIScreen.mainScreen().bounds.width * 0.035, 45, UIScreen.mainScreen().bounds.height * 0.52, 22)

    bottomBarBG.addSubview(playerSlider)

    centerButton = UIButton( frame: CGRectMake( (UIScreen.mainScreen().bounds.width / 2) - 25, 0, 50, 50) )

    centerButton.setImage( UIImage(named: "pause_filled"), forState: .Normal )

    centerButton.setImage( UIImage(named: "play_filled"), forState: .Selected)

    bottomBarBG.addSubview(centerButton)
    view.addSubview(bottomBarBG)
}

func handleSingleTap(recogizer: UITapGestureRecognizer)
{
    if recogizer.view == playerSlider
    {
        isSliderTouched = true
        lastControlTime = CFAbsoluteTimeGetCurrent()

        let translation: CGPoint = recogizer.locationInView(recogizer.view)

        let rate: Double = Double( translation.x / (UIScreen.mainScreen().bounds.size.width * 0.8) )

        playerSlider.value = Float(rate)

        youtubeVideoPlayer.moviePlayer.currentPlaybackTime = Double(youtubeVideoPlayer.moviePlayer.duration) * rate
    }
}

func updateSlider()
{
    if !isSliderTouched
    {
        let value: Float = Float(youtubeVideoPlayer.moviePlayer.currentPlaybackTime / youtubeVideoPlayer.moviePlayer.duration)

        playerSlider.setValue(value, animated: true)
    }
}

func sliderMoveStart()
{
    isSliderTouched = true
}

func sliderMoving()
{
    lastControlTime = CFAbsoluteTimeGetCurrent()

    isSliderTouched = true

    let time: Double = youtubeVideoPlayer.moviePlayer.duration * Double(playerSlider.value)
}

func sliderMoveEnd()
{
    youtubeVideoPlayer.moviePlayer.currentPlaybackTime = youtubeVideoPlayer.moviePlayer.duration * Double(playerSlider.value)
}

func onClick(sender: UIButton)
{
    if sender == centerButton
    {
        lastControlTime = CFAbsoluteTimeGetCurrent()

        if sender.selected
        {
            youtubeVideoPlayer.moviePlayer.play()
            sender.selected = false
        }
        else
        {
            youtubeVideoPlayer.moviePlayer.pause()
            sender.selected = true
        }
    }
}

仅供引用，centerButton 是我的播放/暂停按钮。

谢谢。

Answer 1

在暂停时添加 timer.invalidate() 并在播放时再次为计时器加注星标。