多行文本不适合 UILabel答案

【问题标题】：Multiline text not fitting into UILabel多行文本不适合 UILabel
【发布时间】：2021-03-03 17:28:19
【问题描述】：

我有这个代码：

class ViewController: UIViewController {
    private var nameLabel = UILabel()
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
        updateLable()
    }

    func updateLable ()  {
        nameLabel = UILabel(frame: view.frame)
        nameLabel.text = "Michael Dell Arron Henry Mitchell duve soooooooooooooooooooooooooc"
        nameLabel.backgroundColor = .green
        nameLabel.numberOfLines = 0
        nameLabel.translatesAutoresizingMaskIntoConstraints = false
        self.view.addSubview(nameLabel)
        NSLayoutConstraint.activate([
            nameLabel.centerXAnchor.constraint(equalTo: self.view.centerXAnchor , constant: 0),
            nameLabel.centerYAnchor.constraint(equalTo: self.view.centerYAnchor , constant: 0)
            
        ])
        
        nameLabel.isHidden = false
        
    }

}

我无法将文本放入标签中。我用 numberOfLines = 0 和 sizeToFit() 检查了其他 cmets，但这似乎不起作用。

这是目前的样子：

【问题讨论】：

标签： swift uilabel nslayoutconstraint

【解决方案1】：

您需要限制标签的宽度才能使其换行。您可以：

1。设置宽度约束

NSLayoutConstraint.activate([
    nameLabel.centerXAnchor.constraint(equalTo: self.view.centerXAnchor , constant: 0),
    nameLabel.centerYAnchor.constraint(equalTo: self.view.centerYAnchor , constant: 0),
    nameLabel.widthAnchor.constraint(equalToConstant: 100) /// here!
])

结果：

2。为父视图设置前导和尾随约束

NSLayoutConstraint.activate([
    nameLabel.centerXAnchor.constraint(equalTo: self.view.centerXAnchor , constant: 0), /// you can delete this
    nameLabel.centerYAnchor.constraint(equalTo: self.view.centerYAnchor , constant: 0),
            
    /// here!
    nameLabel.leadingAnchor.constraint(equalTo: self.view.leadingAnchor),
    nameLabel.trailingAnchor.constraint(equalTo: self.view.trailingAnchor)
])

结果：

【讨论】：