UIView 添加手势

    func addSwipe(targetView:UIView)->Void{
        let swipeLeft = UISwipeGestureRecognizer()
        swipeLeft.direction = .left
        swipeLeft.addTarget(self, action: #selector(onSwipeEvt(recognizer:)))
        targetView.addGestureRecognizer(swipeLeft)
        
        let swipeRight = UISwipeGestureRecognizer()
        swipeRight.direction = .right
        swipeRight.addTarget(self, action: #selector(onSwipeEvt(recognizer:)))
        targetView.addGestureRecognizer(swipeRight)
    }
    
    @objc func onSwipeEvt(recognizer:UISwipeGestureRecognizer)->Void{
        if recognizer.direction == .right{
            print("右滑")
        }else if recognizer.direction == .left{
            print("左滑")
        }
    }

通过UISwipeGestureRecognizer.direction 来设置滑动的方向，系统定义方向有：

extension UISwipeGestureRecognizer {
    public struct Direction : OptionSet {
        public init(rawValue: UInt)
        public static var right: UISwipeGestureRecognizer.Direction { get }
        public static var left: UISwipeGestureRecognizer.Direction { get }
        public static var up: UISwipeGestureRecognizer.Direction { get }
        public static var down: UISwipeGestureRecognizer.Direction { get }
    }
}