Implicit and Explicit Bounce Animation Button

UIButton+Animation.swift

extension UIButton {
    func playImplicitBounceAnimation() {
        
        let bounceAnimation = CAKeyframeAnimation(keyPath: "transform.scale")
        bounceAnimation.values = [1.0 ,1.4, 0.9, 1.15, 0.95, 1.02, 1.0]
        bounceAnimation.duration = NSTimeInterval(0.5)
        bounceAnimation.calculationMode = kCAAnimationCubic
        
        layer.addAnimation(bounceAnimation, forKey: "bounceAnimation")
    }
    
    func playExplicitBounceAnimation() {
        
        let bounceAnimation = CAKeyframeAnimation(keyPath: "transform.scale")
        
        var values = [Double]()
        let e = 2.71
        
        for t in 1..<100 {
            let value = 0.6 * pow(e, -0.045 * Double(t)) * cos(0.1 * Double(t)) + 1.0
            
            values.append(value)
        }
        

        bounceAnimation.values = values
        bounceAnimation.duration = NSTimeInterval(0.5)
        bounceAnimation.calculationMode = kCAAnimationCubic
        
        layer.addAnimation(bounceAnimation, forKey: "bounceAnimation")
    }
}