是否有可能在UITextView中找到字符串的每个匹配项并将该匹配项归于属性？

Question

我正在尝试在UITextView中查找字符串的每个匹配项，并将该匹配项归因于此，但在该字符串的首次匹配项后，我将整个textView归因于此。 是否可以找到每次出现的“ hello”的位置并将它们归因于属性而不将整个textView归因于此

func textView(textView: UITextView, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool {

            if textView == self.textView {

        let nsString = textView.text as NSString
        let end = textView.text.characters.count
        let range = NSMakeRange(0, end) as NSRange

        let hString = nsString.rangeOfString("hello")
        let text = NSMutableAttributedString(string: textView.text)

        let cTv = textView.attributedText.mutableCopy() as! NSMutableAttributedString


                if hString.length > 0{


           text.addAttribute(NSForegroundColorAttributeName, value: UIColor.magentaColor(), range: range)


                    cTv.replaceCharactersInRange(range, withAttributedString: text)

        }


                textView.attributedText = text

    }
    return true

}

Answer 1

该系统发送textView(_:shouldChangeTextInRange:replacementText:)它修改之前 textView.text 。 您最好实现textViewDidChange(_:) ，它是系统在修改textView.text 之后发送的。

func textViewDidChange(textView: UITextView) {
    let text = textView.text as NSString
    let richText = NSMutableAttributedString(string: text as String)
    var searchRange = NSMakeRange(0, text.length)
    while true {
        let range = text.rangeOfString("hello", options: [], range: searchRange)
        if range.location == NSNotFound {
            break
        }
        richText.addAttribute(NSForegroundColorAttributeName, value: UIColor.magentaColor(), range: range)
        searchRange.location = range.location + range.length
        searchRange.length = text.length - searchRange.location
    }
    textView.attributedText = richText
}