understanding-responder-chain-pop-quiz.swift

class ResponderViewController: UIViewController {
    
    private var redView = UIView()
    private var greenView = UIView()
    private var blueView = UIView()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        view.subviews(redView.subviews(greenView).subviews(blueView))
        redView.height(300).width(300).centerVertically().centerHorizontally()
        redView.backgroundColor = .red
        
        greenView.height(150).width(150).centerVertically().centerHorizontally()
        greenView.backgroundColor = .green
        
        blueView.height(75).width(75).centerVertically().centerHorizontally()
        blueView.backgroundColor = .blue
        
        let tapRoot = UITapGestureRecognizer(target: self, action: #selector(didTapRoot))
        view.isUserInteractionEnabled = true
        view.addGestureRecognizer(tapRoot)
        
        let tapRed = UITapGestureRecognizer(target: self, action: #selector(didTapRed))
        redView.isUserInteractionEnabled = true
        redView.addGestureRecognizer(tapRed)
    }
    
    @objc private func didTapRoot() {
        print("Root")
    }
    
    @objc private func didTapRed() {
        print("Red")
    }
    
}