UISwipeGestureRecognizer 获取开始和结束位置

Question

In iOS/Swift the UIGestureRecognizer for swiping has location methods that

determine the location where a swipe begin.

I have looked through the doc but I cannot see how to obtain both the start and end location of the swipe. I would like to figure out the (x,y) coordinates within the view of both the start and end. I tried location(ofTouch: ) with different values for ofTouch but that gives me the same value when swiping in the simulator.

Is there a way to do it?

Answer 1

You could subclass UISwipeGestureRecognizer and override touchesMoved . Here, you can simply store the last value:

class MySwipeGestureRecognizer:UISwipeGestureRecognizer {
  var lastTouches:Set<UITouch>?

  override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
    lastTouches = touches
    super.touchesMoved(touches, with:event)
  }
}

Then, when the gesture fires, evaluate the lastTouches property.