CABasicAnimation - transform scale keep in center

Question

Trying to animatie an ellipse masked on a UIView to be scale transformed remaining in the center position.

I have found CALayer - CABasicAnimation not scaling around cen

Answer 1

I have written following function with many added tweaks and options, could be useful for many others.

func layerScaleAnimation(layer: CALayer, duration: CFTimeInterval, fromValue: CGFloat, toValue: CGFloat) {
    let timing = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseIn)
    let scaleAnimation: CABasicAnimation = CABasicAnimation(keyPath: "transform.scale")

    CATransaction.begin()
    CATransaction.setAnimationTimingFunction(timing)
    scaleAnimation.duration = duration
    scaleAnimation.fromValue = fromValue
    scaleAnimation.toValue = toValue
    layer.add(scaleAnimation, forKey: "scale")
    CATransaction.commit()
}

Note: Don't forget to update size after animation completion, because CATransaction reverts back to actual size.