ios - GestureRecogniser 没有响应

Question

初学者 - 下面的代码在 TouchesBegan 函数中运行良好。但不适用于 GestureRecongnizer(滑动或点击)。手势识别器似乎根本没有响应。

我正在研究 swift 2 和 xcode 7.3

override func viewDidLoad()
{ ...
let SwipeUp = UISwipeGestureRecognizer(target: self, action:#selector(ViewController.Dragged(_:)))
   SwipeUp.direction = UISwipeGestureRecognizerDirection.Up
    self.egg.addGestureRecognizer(SwipeUp)
 }
  func Dragged(gesture: UIGestureRecognizer)
{
     UIView.animateWithDuration(0.4, delay: 1.0, options: .CurveEaseOut, animations: {
        let eggFrame = self.egg.frame
        eggFrame.origin.y -= 700
        self.egg.frame = eggFrame
        }, completion: { finished in print("done!") } 
}

Answer 1

您需要保持对 UIGestureRecognizer 的强引用。

var swipeUp: UISwipeGestureRecognizer!

override func viewDidLoad() {
    swipeUp = UISwipeGestureRecognizer(target: self, action:#selector(ViewController.Dragged(_:)))
    swipeUp.direction = UISwipeGestureRecognizerDirection.Up
    self.egg.addGestureRecognizer(swipeUp)
}

func Dragged(gesture: UIGestureRecognizer) {
    UIView.animateWithDuration(0.4, delay: 1.0, options: .CurveEaseOut, animations: {
        let eggFrame = self.egg.frame
        eggFrame.origin.y -= 700
        self.egg.frame = eggFrame
    }, completion: { finished in print("done!") } 
}