added button to sceneKit view but it has a lag

Question

I added a custom button to the sceneKit view. When it is touched, it plays an animation, indicating that it was clicked. The problem I\'m facing is the delay between user touch

Answer 1

For Swift 5

var starButton = UIButton()

    func a ()  {

        starButton = UIButton(type: UIButton.ButtonType.custom)
        starButton.frame = CGRect(x: 100, y: 100, width: 50, height: 50)
        starButton.backgroundColor = .blue
        SpielFenster.addSubview(starButton)

        starButton.addTarget(self, action: #selector(starButtonClicked), for: UIControl.Event.touchDown)
        starButton.adjustsImageWhenHighlighted = false
    }
    @objc func starButtonClicked(){
        animateScaleDown()
    }

    func animateScaleDown(){

        UIView.animate(withDuration: 0.1, animations: {
            self.starButton.transform = CGAffineTransform(scaleX: 0.8, y: 0.8)

        }, completion: { _ in
            self.wait()
        })

    }

    func wait(){
        UIView.animate(withDuration: 0.2, animations: {}, completion: { _ in
            UIView.animate(withDuration: 0.2, animations: {
                self.starButton.transform = CGAffineTransform(scaleX: 1, y: 1)

            })
        })
    }

Answer 2

Okay I solved it. The problematic piece of code is

starButton.addTarget(self, action: "starButtonClicked", forControlEvents: UIControlEvents.TouchUpInside)

UIControlEvent.TouchUpInside gives the illusion of lag. Changing it to .TouchDown is much better.