Xcode9学习笔记76

    override func viewDidLoad() {        super.viewDidLoad()        // Do any additional setup after loading the view, typically from a nib.                let lbl = UILabel(frame: self.view.frame)//创建一个标签对象，它的显示区域和根视图相同                //使用颜色集可以很方便地创建应用程序或页面的主题色，并且可以方便地对主题颜色进行更换        if #available(iOS 11.0, *) {//判断版本兼容性//            lbl.backgroundColor = UIColor(named: "BackgroundClolr")            lbl.textColor = UIColor(named: "ForegroundColor")        }                lbl.text = "www.lisenh.com"        lbl.textAlignment = .center                self.view.addSubview(lbl)    }