override func viewDidLoad() {
        super.viewDidLoad()
        addPanGesture()
    }

    func addPanGesture(){
        let panGesture = UIPanGestureRecognizer(target: self, action: #selector(didSwipeOnView(gesture:)))
        self.view.addGestureRecognizer(panGesture)
    }

    @objc func didSwipeOnView(gesture: UIPanGestureRecognizer) {
        if gesture.state == .ended {
            let velocity = gesture.velocity(in: self.view)

            if velocity.x > 0 {
               print("panning right")

            } else if velocity.x < 0 {
               print("panning left")

            }
        }
    }