swift 笔记

跳转

    let tableViewController = TableViewController();
    tableViewController.test = "参数"
    self.navigationController!.pushViewController(tableViewController, animated:true)

模态跳转

    let tableViewController = TableViewController()
    self.present(tableViewController, animated: true, completion: nil)

跳转后黑屏

    // 设置背景色
    self.view.backgroundColor = UIColor.white

autolayout

    // 创建button-button3并设置样式
    // ...
    // 设置 translates... 为 false，否则无法用 autolayout
    button.translatesAutoresizingMaskIntoConstraints = false
    button2.translatesAutoresizingMaskIntoConstraints = false
    button3.translatesAutoresizingMaskIntoConstraints = false
    // 创建一个控件数组
    let views:[String:AnyObject] = ["button": button,"button2": button2,"button3": button3]
    // 创建水平方向约束
    self.view.addConstraints(NSLayoutConstraint.constraints(
        withVisualFormat: "H:|-5-[button(100)]-5-[button2(100)]",
        options:.alignAllTop,
        metrics: nil,
        views: views
    ))
    // 创建垂直方向约束
    self.view.addConstraints(NSLayoutConstraint.constraints(
        withVisualFormat: "V:|-100-[button(50)]-20-[button3(40)]",
        options:.alignAllLeft,
        metrics: nil,
        views: views
    ))
    // 设置button3宽度
    let constraint:NSLayoutConstraint = NSLayoutConstraint(
        item: button3,
        attribute: .width,
        relatedBy: .equal,
        toItem: nil,
        attribute: .notAnAttribute,
        multiplier: 1.0,
        constant: 140
    )
    // 添加约束
    self.view.addConstraint(constraint)

autolayout 获取不到 size

    // autolayout布局时，控件上下左右需要触碰到边缘，否则无法获取 size
    // 如:
    // H:|[box(40)]|
    // V:|-80-[box(999)]-80-|
    // 获取 size 要在 viewDidLayoutSubviews 方法内
    override func viewDidLayoutSubviews() {
        scrollView.contentSize = box.frame.size
    }

tableView 设置数据

    // 在协议中设置数据源(UITableViewDataSource)，代理(UITableViewDelegate)
    class TableViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
        var table:UITableView!
        let arr:[String] = ["我是谁", "我从哪里来", "要到哪里去"]
        func setTableView() {
            let rect = self.view.frame
            table = UITableView(frame: rect)
            self.view.addSubview(table)
            //设置数据源
            self.table.dataSource = self
            //设置代理
            self.table.delegate = self
            //注册UITableView，cellID为重复使用cell的Identifier
            self.table.register(UITableViewCell.self, forCellReuseIdentifier: "cellID")
        }
        func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
            return arr.count
        }
        //设置section的数量
        func numberOfSections(in tableView: UITableView) -> Int {
            return 1
        }
        //设置tableview的cell
        func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
            let cell = (table.dequeueReusableCell(withIdentifier: "cellID", for: indexPath)) as UITableViewCell
            // cell.textLabel?.text = arr[indexPath.row]
            
            
            let button = UIButton()
            button.setTitle("测试\(indexPath.row)", for: .normal)
            button.backgroundColor = UIColor.black
            button.addTarget(self, action: #selector(clickButton(_:)), for: .touchUpInside)
            button.tag = indexPath.row
            cell.addSubview(button)
            let views:[String:AnyObject] = ["button": button]
            button.translatesAutoresizingMaskIntoConstraints = false
            //创建水平方向约束
            cell.addConstraints(NSLayoutConstraint.constraints(
                withVisualFormat: "H:|-5-[button]-5-|",
                options:.alignAllTop,
                metrics: nil,
                views: views
            ))
            cell.addConstraints(NSLayoutConstraint.constraints(
                withVisualFormat: "V:|-10-[button]",
                options:.alignAllLeft,
                metrics: nil,
                views: views
            ))
            return cell
        }
        // 点击事件
        @objc func clickButton (_ test: UIButton) {
            print(arr[test.tag])
        }
        
        override func viewDidLoad() {
            super.viewDidLoad()
            self.setTableView()
        }
    }