ios - UIView.animateWithDuration 或 UIScrollView.animateWithDuration - 如何在当前状态暂停

Question

我正在使用这些(代码块 1 和 2)将带有动画的 UIScrollView 从开始移动到我的结束点(x:0 到 1000，在这个例子中)

代码块 1:

UIScrollView.animateWithDuration(Double(5), delay: 1, options: (UIViewAnimationOptions.AllowUserInteraction | UIViewAnimationOptions.CurveLinear | UIViewAnimationOptions.BeginFromCurrentState),
                            animations: {
self.myScrollView.contentOffset = CGPointMake(1000, 0)
                            },
                            completion: {
                                finished in
                                if(finished)
                                {

                                }
                        })

代码块 2:

UIView.animateWithDuration ...

问题是不能在当前x点暂停。

我已经尝试过了，但对我不起作用。

• 导入 QuartzCore 框架
• self.myScrollView.layer.beginTime = 0.0 完成

• CATransaction.begin() 和 CATransaction.commit()

• self.myScrollView.layer.removeAllAnimations()。这将完全停止动画，然后 UIScrollView 将到达终点(到 x:1000)

同时 animateWithDuration 正在取消 scrollViewDidScroll，因此无法获取当前位置。另外，同样的原因无法在Pause函数中获取到当前位置。

func scrollViewDidScroll(scrollView: UIScrollView)
{
scrollView.bounds.origin.x
var pos:CGPoint = self.layer.presentationLayer().bounds.origin
}

func StopSlidingByBeginDragging()
{
CATransaction.begin() 
self.myScrollView.layer.removeAllAnimations()
CATransaction.commit()
}

基本上，当我手动触摸或滚动 UIScrollView 时，我需要暂停它应该暂停然后恢复。我发现这个动画是滑动动画，也许你可以建议一些不同的东西。

谢谢

Answer 1

试试这个自定义 UIScrollView 类以及 UIViewController 代码。

class TouchScrollView : UIScrollView
{
    var animatedScrollOffset = CGPointMake(0, 0)

    func startAnimation()
    {
        UIScrollView.animateWithDuration(Double(5), delay: 1,
            options: (UIViewAnimationOptions.AllowUserInteraction
                | UIViewAnimationOptions.CurveLinear |
                UIViewAnimationOptions.BeginFromCurrentState),
            animations: {
                self.contentOffset = self.animatedScrollOffset
            },
            completion: {
                finished in
                if !finished {

                }
        })

    }

    func stopAnimation()
    {
        let offset = self.layer.presentationLayer().bounds.origin
        self.layer.removeAllAnimations()
        self.contentOffset = offset
    }

    override init(frame: CGRect) {
        super.init(frame: frame)

       if let gestures = self.gestureRecognizers
        {
            for gestureRecognizer in gestures
            {
                if let swipeRecognizer = gestureRecognizer as? UIGestureRecognizer
                {
                    swipeRecognizer.cancelsTouchesInView = false
                }
            }
        }
    }

    required init(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
    }
    override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
        self.stopAnimation()
    }

    override func touchesEnded(touches: NSSet, withEvent event: UIEvent) {
        self.startAnimation()
    }
}


class ViewController: UIViewController, UITextViewDelegate,UIScrollViewDelegate {

    @IBOutlet var scrollView : TouchScrollView!

    override func viewDidLoad() {

        scrollView.contentSize = CGSizeMake(scrollView.frame.width, 10000)
        scrollView.backgroundColor = UIColor.redColor()
        scrollView.showsVerticalScrollIndicator = true
        scrollView.showsHorizontalScrollIndicator = true
        scrollView.animatedScrollOffset = CGPointMake(0, 1000)
        scrollView.startAnimation()
        scrollView.delegate = self
    }

    func scrollViewWillBeginDragging(_: UIScrollView) {
        println("begin dragging")
        scrollView.stopAnimation()
    }

    func scrollViewDidEndDragging(_ : UIScrollView, willDecelerate decelerate: Bool) {
        println("end dragging")
        if !decelerate
        {
            scrollView.startAnimation()
        }
    }

    func scrollViewDidEndDecelerating(_ : UIScrollView) {
        scrollView.startAnimation()
    }

}