ios - TextView 不显示在 ScrollView 上

Question

我有一个 View Controller 名称为 TeamDetailsViewController。我以编程方式将 ScrollView 添加到 View Controller ，并将 UITextview 添加为 ScrollView 的 subview 。但由于未知原因， TextView 没有显示。请帮忙。这是我的代码

class TeamDetailsController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        navigationController?.navigationBar.prefersLargeTitles = false

        setupViews()
    }

    lazy var scrollView: UIScrollView = {
        let sv = UIScrollView(frame: self.view.bounds)
        sv.backgroundColor = .blue

        sv.autoresizingMask = UIViewAutoresizing(rawValue: UIViewAutoresizing.RawValue(UInt8(UIViewAutoresizing.flexibleWidth.rawValue) | UInt8(UIViewAutoresizing.flexibleHeight.rawValue)))

        sv.contentSize = CGSize(width: self.view.bounds.size.width, height: self.view.bounds.size.height * 2);
        return sv
    }()

    var textView: UITextView = {
        var tv = UITextView()
        tv.textColor = .darkGray
        tv.backgroundColor = .black
        tv.font = UIFont.systemFont(ofSize: 16)
        return tv
    }()

    func setupViews() {

        view.backgroundColor = .white
        view.addSubview(scrollView)            
        scrollView.addSubview(textView)

        scrollView.addConstraintsWithFormat(format: "H:|-16-[v0]-16-|", views: textView)
        scrollView.addConstraintsWithFormat(format: "V:|-16-[v0]-16-|", views: textView)           
    }
}

Answer 1

试试这个代码；

    var textView: UITextView = {
    var tv = UITextView()
    tv.textColor = .darkGray
    tv.backgroundColor = .black
tv.translatesAutoresizingMaskIntoConstraints = false
    tv.font = UIFont.systemFont(ofSize: 16)
    return tv
}()