[Xcode 实际操作]七、文件与数据-(19)颜色集(Color Set)的使用

 1 import UIKit
 2 
 3 class ViewController: UIViewController {
 4 
 5     override func viewDidLoad() {
 6         super.viewDidLoad()
 7         // Do any additional setup after loading the view, typically from a nib.
 8         
 9         //创建一个标签对象，它的显示区域和根视图相同，
10         let lbl = UILabel(frame: self.view.frame)
11         
12         //添加一个版本兼容性的判断语句
13         if #available(iOS 11.0, *)
14         {
15             //分别设置两个颜色集合
16             //作为标签对象的背景颜色
17             lbl.backgroundColor = UIColor(named: "BackgroundColor")
18             //作为标签对象的文字颜色
19             lbl.textColor = UIColor(named:"ForegroundColor")
20         }
21         
22         //设置标签对象的文字内容
23         lbl.text = "https://www.cnblogs.com/strengthen/"
24         //设置标签对象的文字对齐方式
25         lbl.textAlignment = .center
26         
27         //将标签对象添加到当前视图控制器的根视图
28         self.view.addSubview(lbl)
29     }
30     
31     override func didReceiveMemoryWarning() {
32         super.didReceiveMemoryWarning()
33         // Dispose of any resources that can be recreated.
34     }
35 }