如何计算UITextView中文本的高度？

Question

我怎么知道这个textView里面文字的高度？

lazy var textView: UITextView = {
    let tv = UITextView()
    tv.textColor = .white
    tv.translatesAutoresizingMaskIntoConstraints = false
    tv.isEditable = false
    tv.backgroundColor = .white
    tv.text = "Se non vuoi vedere di nuovo questa presentazione clicca sul bottone qui sotto..."
    tv.textAlignment = .center
    tv.font = UIFont(name: "Avenir-Light", size: 22)
    return tv
}()

Answer 1

你可以像下面这样计算文字高度:

let sizeThatFitsTextView = textView.sizeThatFits(CGSize(width: textView.frame.size.width, height: CGFloat(MAXFLOAT)))
let heightOfText = sizeThatFitsTextView.height