How to detect a flick gesture using UISwipeGestureRecognizer?

问题

I heard that UISwipeGestureRecognizer can be used to distinguish between a slow swipe and a fast flick. But I can't find any API to tell the difference.

回答1:

Do you specifically need to use UISwipeGestureRecognizer, or can you use UIPanGestureRecognizer instead? UIPanGestureRecognizer gives you precise movement data whereas UISwipeGestureRecognizer is more basic and just detects whether or not a swipe happened (and in which direction).

UIPanGestureRecognizer has a -velocityInView: method which returns a CGPoint, expressing points per second, vertically and horizontally.

回答2:

You should use Pan Gesture and find out velocity for better accuracy.

Here is code snip for PanGesture in Swift 5

//Add Pan Gesture on target view in viewDidLoad
        let panGesture = UILongPressGestureRecognizer(target: self, action: #selector(self.panGestureDetected))
        view.addGestureRecognizer(panGesture)

@objc func panGestureDetected()
    {
        print("Pan Gesture detected!!")
    }

来源：https://stackoverflow.com/questions/21487750/how-to-detect-a-flick-gesture-using-uiswipegesturerecognizer