  
  lazy var stopSpotlightButton: UIButton = {
    let button = UIButton(frame: CGRect(x: 20, y: UIScreen.main.bounds.height - 160,
                                        width: UIScreen.main.bounds.width - 40, height: 40))
    button.backgroundColor = .white
    button.setTitle("Stop Spotlight", for: .normal)
    button.setTitleColor(UIColor.blue, for: .normal)
    button.setTitleColor(UIColor.darkGray, for: .highlighted)
    button.addTarget(self, action: #selector(onClickStopSpotlightButton), for: .touchUpInside)
    return button
  }()
  
  lazy var nextButton: UIButton = {