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)
    }