ios - 确定 UITextView 将截断字符串的位置

Question

我有一个带有长字符串的 UITextView。 TextView 大小由自动布局决定，并设置为尾部截断文本。它看起来像这样:

如何确定显示的字符串范围和被截断的范围？

Answer 1

试试这个

class ViewController: UIViewController ,NSLayoutManagerDelegate{

@IBOutlet weak var textView: UITextView!
var range :NSRange!
override func viewDidLoad() {
    super.viewDidLoad()


    textView.textContainer.layoutManager?.delegate = self
    let str = textView.text as NSString
    //Regardless of the repeated string
    range = str.rangeOfString("cillium adipisicing")
    print(range)


}

// Invoked while determining the soft line break point.  When NO, NSLayoutManager tries to find the next line break opportunity before charIndex
func layoutManager(layoutManager: NSLayoutManager, shouldBreakLineByWordBeforeCharacterAtIndex charIndex: Int) -> Bool{

    // charIndex is in the string or not
    if range.location != NSNotFound && NSLocationInRange(charIndex, NSRange(location: range.location + 1, length: range.length - 1 )) {
        print("range of string is truncated -> charIndex is \(charIndex)")
    }
    return  true
}
}

但仅限于 BreakLineByWord 如果没有 ""的单词被截断，charIndex 为 0

希望对您有所帮助:)