Swift UIKit 多页面

多页面

根据需要建立以.swift档案，并各自命名 如：IntroViewController、ArticleViewController及ArticleDetailViewController
在viewDidLoad() 中定义底色、页面Label、以及UIButton

定义底色 self.view.backgroundColor = UIColor.white

定义页面标题

` let myLabel = UILabel(frame: CGRect(x: 0, y: 0, width: fullSize.width, height: 40))
        myLabel.center = CGPoint(x: fullSize.width * 0.5, y: fullSize.height * 0.08)
        myLabel.textAlignment = .center
        myLabel.text = "首頁"
        self.view.addSubview(myLabel)`

定义需要跳转页面的UIButton

定义 var变量 myButton

` var myButton = UIButton(frame: CGRect(x: 0, y: 0, width: 100, height: 30))`

设置标题、背景颜色、位置

 myButton.setTitle("Article", for: .normal)
 myButton.backgroundColor = UIColor.lightGray
 myButton.center = CGPoint(x: fullSize.width * 0.5, y: fullSize.height * 0.2)

操作动作关联，建立前往 Article 页面的UIButton

 myButton.addTarget(nil, action: #selector(ViewController.goArticle), for: .touchUpInside)

Quick Help中addTarget的用法

以及

 self.view.addSubview(myButton)

在ViewController中加上按下按钮执行动作的方法：

    @objc func goArticle() {
        let articleVC = ArticleViewController()
        self.present(articleVC, animated: true, completion: nil)
    }

Quick Help中present的用法

页面开启退出的过程

在页面开启及退出的各个阶段，都可以加入自定义的程式

在首页ViewController中定义

 override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        mylabel.text = "hello"
        print("viewWillAppear")
    }
    
    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
        
        print("viewDidAppear")
    }
    
    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        
        print("viewWillDisappear")
    }

    override func viewDidDisappear(_ animated: Bool) {
        super.viewDidDisappear(animated)
        
        print("viewDidDisappear")
    }