Changing a CAShapeLayer path

Question

I have a button I would like to scale according to the frame size. However, when I change the underlying CALayer paths they do not get updated. In the updateLayerProperites function I use CALayer'a setValue function to change the path. I have also tried setting the path property directly with kiteShape.path = kitePath.CGPath but that does not work either. How can I scale the drawing?

import UIKit  

@IBDesignable
class ElementButton: UIButton {

    var leftKiteShape: CAShapeLayer!
    var kiteShape: CAShapeLayer!
    var rightKiteShape: CAShapeLayer!

    override init(frame: CGRect) {
        super.init(frame: frame)
        createLayers()
        updateLayerProperties()
    }    

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

    override func layoutSubviews() {
        super.layoutSubviews()
        createLayers()
        updateLayerProperties()
    }

    @IBInspectable
    var lineWidth: CGFloat = 1 {
        didSet {
            updateLayerProperties()
        }
    }

    private func createLayers() {
        if kiteShape == nil {
            //// Kite Drawing
            let kitePath = UIBezierPath()
            kitePath.moveToPoint(CGPointMake(frame.minX + 48, frame.minY + 5))
            kitePath.addLineToPoint(CGPointMake(frame.minX + 28, frame.minY + 68))
            kitePath.addLineToPoint(CGPointMake(frame.minX + 48, frame.minY + 93))
            kitePath.addLineToPoint(CGPointMake(frame.minX + 68, frame.minY + 68))
            kitePath.addLineToPoint(CGPointMake(frame.minX + 48, frame.minY + 5))
            kitePath.closePath()

            kiteShape = CAShapeLayer()
            kiteShape.path = kitePath.CGPath
            kiteShape.strokeColor = UIColor.blackColor().CGColor
            kiteShape.lineWidth = lineWidth
            kiteShape.opacity = 0.5
            self.layer.addSublayer(kiteShape)
        }    

        if leftKiteShape == nil {
            //// LeftKite Drawing
            let leftKitePath = UIBezierPath()
            leftKitePath.moveToPoint(CGPointMake(frame.minX + 46, frame.minY + 4.25))
            leftKitePath.addLineToPoint(CGPointMake(frame.minX + 24, frame.minY + 68))
            leftKitePath.addLineToPoint(CGPointMake(frame.minX + 45, frame.minY + 92.75))
            leftKitePath.addLineToPoint(CGPointMake(frame.minX + 6, frame.minY + 68))
            leftKitePath.addLineToPoint(CGPointMake(frame.minX + 46, frame.minY + 4.25))
            leftKitePath.closePath()

            leftKiteShape = CAShapeLayer()
            leftKiteShape.path = leftKitePath.CGPath
            leftKiteShape.strokeColor = UIColor.blackColor().CGColor
            leftKiteShape.lineWidth = lineWidth
            leftKiteShape.opacity = 0.5
            self.layer.addSublayer(leftKiteShape)
        }    


        if rightKiteShape == nil {
            //// RightKite Drawing
            let rightKitePath = UIBezierPath()
            rightKitePath.moveToPoint(CGPointMake(frame.minX + 50, frame.minY + 4.25))
            rightKitePath.addLineToPoint(CGPointMake(frame.minX + 72, frame.minY + 68))
            rightKitePath.addLineToPoint(CGPointMake(frame.minX + 51, frame.minY + 92.75))
            rightKitePath.addLineToPoint(CGPointMake(frame.minX + 90, frame.minY + 68))
            rightKitePath.addLineToPoint(CGPointMake(frame.minX + 50, frame.minY + 4.25))
            rightKitePath.closePath()

            rightKiteShape = CAShapeLayer()
            rightKiteShape.path = rightKitePath.CGPath
            rightKiteShape.strokeColor = UIColor.blackColor().CGColor
            rightKiteShape.lineWidth = lineWidth
            rightKiteShape.opacity = 0.5
            self.layer.addSublayer(rightKiteShape)
        }
    }

    private func updateLayerProperties() {
        let kitePath = UIBezierPath()
        kitePath.moveToPoint(CGPointMake(frame.minX + 48, frame.minY + 5))
        kitePath.addLineToPoint(CGPointMake(frame.minX + 28, frame.minY + 68))
        kitePath.addLineToPoint(CGPointMake(frame.minX + 48, frame.minY + 93))
        kitePath.addLineToPoint(CGPointMake(frame.minX + 68, frame.minY + 68))
        kitePath.addLineToPoint(CGPointMake(frame.minX + 48, frame.minY + 5))
        kitePath.closePath()

        kiteShape.setValue(kitePath.CGPath, forKey: "path")
        kiteShape.setValue(lineWidth, forKey: "lineWidth")    

        let leftKitePath = UIBezierPath()
        leftKitePath.moveToPoint(CGPointMake(frame.minX + 46, frame.minY + 4.25))
        leftKitePath.addLineToPoint(CGPointMake(frame.minX + 24, frame.minY + 68))
        leftKitePath.addLineToPoint(CGPointMake(frame.minX + 45, frame.minY + 92.75))
        leftKitePath.addLineToPoint(CGPointMake(frame.minX + 6, frame.minY + 68))
        leftKitePath.addLineToPoint(CGPointMake(frame.minX + 46, frame.minY + 4.25))
        leftKitePath.closePath()    

        leftKiteShape.setValue(leftKitePath.CGPath, forKey: "path")
        leftKiteShape.setValue(lineWidth, forKey: "lineWidth")

        let rightKitePath = UIBezierPath()
        rightKitePath.moveToPoint(CGPointMake(frame.minX + 50, frame.minY + 4.25))
        rightKitePath.addLineToPoint(CGPointMake(frame.minX + 72, frame.minY + 68))
        rightKitePath.addLineToPoint(CGPointMake(frame.minX + 51, frame.minY + 92.75))
        rightKitePath.addLineToPoint(CGPointMake(frame.minX + 90, frame.minY + 68))
        rightKitePath.addLineToPoint(CGPointMake(frame.minX + 50, frame.minY + 4.25))
        rightKitePath.closePath()    

        rightKiteShape.setValue(rightKitePath.CGPath, forKey: "path")
        rightKiteShape.setValue(lineWidth, forKey: "lineWidth")
    }

    private func disableTouch() {
        self.userInteractionEnabled = false
    }

    private func enableTouch() {
        self.userInteractionEnabled = true
    }


}