Animating CALayer's shadowPath property

Question

I am aware that a CALayer\'s shadowPath is only animatable using explicit animations, however I still cannot get this to work. I suspect that I am not passing the toVa

Answer 1

let cornerRadious = 10.0
        //
        let shadowPathFrom = UIBezierPath(roundedRect: rect1, cornerRadius: cornerRadious)
        let shadowPathTo = UIBezierPath(roundedRect: rect2, cornerRadius: cornerRadious)
        //
        layer.masksToBounds = false
        layer.shadowColor = UIColor.yellowColor().CGColor
        layer.shadowOpacity = 0.6
        //
        let shadowAnimation = CABasicAnimation(keyPath: "shadowPath")
        shadowAnimation.fromValue = shadowPathFrom.CGPath
        shadowAnimation.toValue = shadowPathTo.CGPath
        shadowAnimation.duration = 0.4
        shadowAnimation.autoreverses = true
        shadowAnimation.removedOnCompletion = true
        shadowAnimation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)
        layer.addAnimation(shadowAnimation, forKey: "shadowAnimation")