Ios 更新NSLinguisticTagSchemeLanguage

你好，我现在正在做一个项目，我必须支持我的标签rtl文本

我有一个用swift 3编写的片段，但它不再适用于swift 4和5。我试图更新它，但我不知道如何更新它

extension UILabel {
func decideTextDirection () {
    let tagScheme = [NSLinguisticTagSchemeLanguage]
    let tagger    = NSLinguisticTagger(tagSchemes: tagScheme, options: 0)
    tagger.string = self.text
    let lang      = tagger.tag(at: 0, scheme: NSLinguisticTagSchemeLanguage,
                                      tokenRange: nil, sentenceRange: nil)

    if lang?.range(of:"ar") != nil {
        self.textAlignment = NSTextAlignment.right
    } else {
        self.textAlignment = NSTextAlignment.left
    }
}

要使用此标签，请在标签上添加以下内容：

detailLabel.text = details[0]

detailLabel.decideTextDirection()

---

我把你的扩展扔到操场上，把编译器的错误敲定了。以下是我的想法：

extension UILabel {
    func decideTextDirection () {
        let tagScheme = [NSLinguisticTagScheme.language]
        let tagger = NSLinguisticTagger(tagSchemes: tagScheme, options: 0)
        tagger.string = self.text
        let lang = tagger.tag(at: 0, scheme: NSLinguisticTagScheme.language,
                                   tokenRange: nil, sentenceRange: nil)

        if let _ = lang?.rawValue.contains("ar") {
            self.textAlignment = NSTextAlignment.right
        } else {
            self.textAlignment = NSTextAlignment.left
        }
    }
}