ios - UILabel 文本截断与文本换行

Question

我有一个 UILabel 作为 titleView 放在导航栏中。我希望它有 2 行，其中第一行可以被截断，第二行居中对齐。

在代码中它看起来更不像这样:

    let label = UILabel()
    let text = NSAttributedString(string: "Long long long text\nsecond line")
    label.attributedText = text
    label.textAlignment = .Center
    label.numberOfLines = 0
    label.lineBreakMode = .ByTruncatingTail
    label.sizeToFit()

    self.navigationItem.titleView = label

The effect in case of the first line text is not exceeding available space is like this:

It's pretty good, but when the first line text is longer than:

let text = NSAttributedString(string: "Very very very very very long text\nsecond line")

I want to achieve like below.

如何实现？我尝试了 numberOfLines 和 lineBreakMode，但没有用。

Answer 1

将换行模式更改为 ByTruncatingMiddle 而不是 ByTruncatingTail。像下面这样的东西，

    label.lineBreakMode = .ByTruncatingMiddle

希望这会有所帮助:)