A lighter way of discovering text writing direction

Question

I want to determine the writing direction of a string so that I can render Right-to-Left languages such as Arabic correctly in a CALayer.

so I have this method

Answer 1

Swift

For me the .natural textAlignment of UITextView did not work unless I edited the text and line from start.

Based on the great answer to this question and the comment below it.

let text = "..."
let lang = CFStringTokenizerCopyBestStringLanguage(text as CFString, CFRange(location: 0, length: text.characters.count))

if let lang = lang {
    let direction = NSLocale.characterDirection(forLanguage: lang as String)

    if direction == .rightToLeft {
        textView.textAlignment = .right
    }
    else {
        textView.textAlignment = .left
    }
}