Resizing Sprite Kit Node using Pinch Gesture

Question

I'm trying to implement pinch gesture recognizer to resize my sprite node. I'm using setScale(sender.scale) to do that, but every time I lift my fingers and try to pinch again, my sprite reset to 1.0 scale before scaling to the pinch again.

What I want is when I re-pinch the screen, the sprite size stays as it is, and it grow bigger as I pinch out or smaller as I pinch in, so I can keep pinching to make it as big or as small as it can. How to do this?

Here's my code.

var pizza = PizzaSprite()

override func didMove(to view: SKView) {

    let pinchGesture = UIPinchGestureRecognizer(target: self, action: #selector(self.handlePinchFrom(_:)))

    pizza = PizzaSprite(size: self.frame.width * 0.25)

    self.addChild(pizza)

    self.view?.addGestureRecognizer(pinchGesture)

}

func handlePinchFrom(_ sender: UIPinchGestureRecognizer) {

    if sender.state == .began {

    } else if sender.state == .changed {

        pizza.setScale(sender.scale)

    } else if sender.state == .ended {

    }

}

Here's the PizzaSprite class

init() {
    let texture = SKTexture(imageNamed: "demPizza")
    super.init(texture: texture, color: UIColor.clear, size: texture.size())
}

init(size: CGFloat) {
    let texture = SKTexture(imageNamed: "demPizza")
    super.init(texture: texture, color: UIColor.clear, size: CGSize(width: size, height: size))
}


required init?(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
}

Answer 1

So, I've been working at this for a week now, been given up once and use only pan instead, but I had to retry using pinch. Just some minutes after I posted this question, I got the answer myself....

I'm posting here in case someone need this.

func handlePinchFrom(_ sender: UIPinchGestureRecognizer) {

    let pinch = SKAction.scale(by: sender.scale, duration: 0.0)

    pizza.run(pinch)
    sender.scale = 1.0

}