突出显示 UILabel 中的子字符串

Question

我无法突出显示 substring.Here 是我所做的（是一个 "duplicate" 问题）：

这是我需要将其转换为 NSRange

的地方

for user in tweet.userMentions
{          
    let userName = user.keyword
    if let startIndex = tweetTextLabel.text?.rangeOfString("@")?.startIndex
    {
        let range = startIndex...userName.endIndex
        var atrString = NSMutableAttributedString(string:tweetTextLabel.text!)
        atrString.addAttribute(NSForegroundColorAttributeName, value: UIColor.redColor(), range: range as? NSRange)
        tweetTextLabel.attributedText = atrString
    }
}

我能做什么？？也许这是 swift 的另一个功能我正在使用 swift 1.1，iOS 8.1 SDK

更新仍然没有突出显示文本

 for user in tweet.userMentions{

                let text = tweetTextLabel.text!
                let nsText = text as NSString
                let textRange = NSMakeRange(0, nsText.length)
                let attributedString = NSMutableAttributedString(string: nsText)

                nsText.enumerateSubstringsInRange(textRange, options: NSStringEnumerationOptions.ByWords, { (substring, substringRange, enclosingRange, stop) -> () in

                    if (substring == user.keyword) {
                        attributedString.addAttribute(NSForegroundColorAttributeName, value: UIColor.blueColor(), range: substringRange)
                        println(substring)
                    }
                })
                tweetTextLabel.attributedText = attributedString
                println(attributedString)

再次更新 所以我更新代码的地方仍然没有为子字符串着色我正在做一个推特应用程序，它用颜色标签、网址和用户屏幕名称突出显示

Answer 1

我不太明白你想做什么，但这里有一个供你工作的模型：

let s = "Eat @my shorts" as NSString
var att = NSMutableAttributedString(string: s as String)
let r = s.rangeOfString("@\w.*?\b", options: .RegularExpressionSearch, range: NSMakeRange(0,s.length))
if r.length > 0 {
    att.addAttribute(NSForegroundColorAttributeName, value: UIColor.redColor(), range: r)
}

这给出了一个属性字符串 "Eat @my shorts"，其中单词“@my”是红色的。

希望提供线索...

Answer 2

更新@matt 的精彩回答，Swift 4:

 let s = "Eat @my shorts" as NSString
 let att = NSMutableAttributedString(string: s as String)
 let r = s.range(of: "@\w.*?\b", options: .regularExpression, range: NSMakeRange(0,s.length))
    if r.length > 0 { att.addAttribute(NSAttributedStringKey.foregroundColor, value: UIColor.red, range: r)
        }

Answer 3

在 swift 4 中查找此扩展程序：

extension UILabel {

    func highlight(searchedText: String?, color: UIColor = .red) {
        guard let txtLabel = self.text?.lowercased(), let searchedText = searchedText?.lowercased() else {
            return
        }

        let attributeTxt = NSMutableAttributedString(string: txtLabel)
        let range: NSRange = attributeTxt.mutableString.range(of: searchedText, options: .caseInsensitive)

        attributeTxt.addAttribute(NSAttributedString.Key.foregroundColor, value: color, range: range)

        self.attributedText = attributeTxt
    }

}

编辑：扩展改进，他可以接收 String

的参数

 extension UILabel {

    func highlight(searchedText: String?..., color: UIColor = .red) {
        guard let txtLabel = self.text else { return }

        let attributeTxt = NSMutableAttributedString(string: txtLabel)

        searchedText.forEach {
            if let searchedText = [=11=]?.lowercased() {
                let range: NSRange = attributeTxt.mutableString.range(of: searchedText, options: .caseInsensitive)

                attributeTxt.addAttribute(NSAttributedString.Key.foregroundColor, value: color, range: range)
                attributeTxt.addAttribute(NSAttributedString.Key.font, value: UIFont.boldSystemFont(ofSize: self.font.pointSize), range: range)
            }
        }

        self.attributedText = attributeTxt
    }

}

Answer 4

Swift5 版本，适用于 Font 和 Color

extension UILabel {
    func highlight(text: String?, font: UIFont? = nil, color: UIColor? = nil) {
        guard let fullText = self.text, let target = text else {
            return
        }

        let attribText = NSMutableAttributedString(string: fullText)
        let range: NSRange = attribText.mutableString.range(of: target, options: .caseInsensitive)
        
        var attributes: [NSAttributedString.Key: Any] = [:]
        if let font = font {
            attributes[.font] = font
        }
        if let color = color {
            attributes[.foregroundColor] = color
        }
        attribText.addAttributes(attributes, range: range)
        self.attributedText = attribText
    }
}

突出显示 UILabel 中的子字符串

Highlighting a substring in a UILabel

twitter

uitableview

ios

swift