ios - Touch up 和 Touch down 操作 UIImageView

Question

我想要实现的是当用户触摸 UIImageView 时设置 Image1，当用户抬起他的手指时设置 Image2。

我只能得到 UIGestureRecognizerState.Ended with this code

var tap = UITapGestureRecognizer(target: self, action: Selector("tappedMe:"))     
imageView.addGestureRecognizer(tap)
imageView.userInteractionEnabled = true
   
func tappedMe(gesture: UITapGestureRecognizer)
{
    
    if gesture.state == UIGestureRecognizerState.Began{
        imageView.image=originalImage
        dbgView.text="Began"
    }else if  gesture.state == UIGestureRecognizerState.Ended{
        imageView.image=filteredImage
        dbgView.text="Ended"
    }else if  gesture.state == UIGestureRecognizerState.Cancelled{
        imageView.image=filteredImage
        dbgView.text="Cancelled"
    }else if  gesture.state == UIGestureRecognizerState.Changed{
        imageView.image=filteredImage
        dbgView.text="Changed"
    }

}

Answer 1

UITapGestureRecognizer 不会将其状态更改为 .Began，但 UILongPressGestureRecognizer 会。如果您出于某种原因字体想要直接覆盖触摸回调，您可以使用具有非常短的 minimumPressDuration(例如 0.1)的 UILongPressGestureRecognizer 来实现效果。

@Daij-Djan 的例子:

class ViewController: UIViewController {
  override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view, typically from a nib.

    var tap = UILongPressGestureRecognizer(target: self, action: Selector("pressedMe:"))
    tap.minimumPressDuration = 0
    self.view.addGestureRecognizer(tap)
    self.view.userInteractionEnabled = true
  }

  func pressedMe(gesture: UITapGestureRecognizer) {
    if gesture.state == .Began{
      self.view.backgroundColor = UIColor.blackColor()
    } else if  gesture.state == .Ended {
      self.view.backgroundColor = UIColor.whiteColor()
    }
  }
}