아미(아름다운미소)

nil 전달 함수 var lampOn:Bool? = false func lampOnOffRemove(isOn : Bool?) { if let onOff = isOn { self.lampOn = onOff self.lampImageView.image = UIImage(named : onOff ? "lamp-on.png" : "lamp-off.png") } else { self.lampOn = nil self.lampImageView.image = UIImage(named : "lamp-remove.png") } } @IBAction func lampOffClicked(_ sender: AnyObject) { if lampOn! { //