import UIKit
import PlaygroundSupport

class Target {

    @objc func changeColor(sender: UIButton?) {

        guard let button = sender else { return }

        button.backgroundColor = UIColor.purple
    }
}

let viewController = UIViewController()
viewController.view.frame = CGRect(x: 0, y: 0, width: 200, height: 200)
viewController.view.backgroundColor = UIColor.red

let v = UIView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
v.backgroundColor = UIColor.green

let l = UILabel(frame: CGRect(x: 0, y: 0, width:0, height: 0))
l.text = "Hello"

viewController.view.addSubview(v)
v.addSubview(l)
l.sizeToFit()

let layer = CALayer()


layer.borderWidth = 1.0
layer.borderColor = UIColor.red.cgColor

let anim = CABasicAnimation(keyPath: "bounds")
anim.duration = 1.0
anim.fillMode = kCAFillModeForwards
anim.fromValue = CGRect(x: 0, y: 0, width: 10, height: 10)
anim.toValue = CGRect(x: 0, y: 0, width: 100, height: 100)
anim.isRemovedOnCompletion = true

layer.add(anim, forKey: "bounds")

v.layer.addSublayer(layer)
layer.bounds = CGRect(x: 0, y: 0, width: 100, height: 100)


let b = UIButton(type: .system)
b.setTitle("Press Me", for: .normal)
b.titleLabel?.textColor = UIColor.blue

b.frame = CGRect(x: 100, y: 100, width: 0, height: 0)
b.sizeToFit()

viewController.view.addSubview(b)

let target = Target()
b.addTarget(target, action: #selector(target.changeColor(sender:)), for: .touchUpInside)

PlaygroundPage.current.liveView = viewController.view