why (arabic with english) text refuses to align right?

Question

This is the string I use:

CASE 1

    var word1 = "عبد الله"
    var word2 = "restaurant"
    label.text = " \(word1) found your review on \(word2) useful."

Result:

CASE 2

    var word1 = "عبد الله"
    var word2 = "restaurant"
    label.text = "note: \(word1) found your review on \(word2) useful."

Result:

Question

so, how do I make the first word to wrap right? if the first word is arabic, it gets wrapped to the left, but if the first word is english the situation is expected, so how make the word1 to show up when first word on the left?

I tried both

label.textAlignment = NSTextAlignment.Left

and

label.textAlignment = NSTextAlignment.Natural

without any luck.

Answer 1

Unicode has two marker characters (LTR: 0x200E, RTL:200F). These are invisible, but control the direction, I just need to add this \u{200E} to force the wrapping direction.

 \u{200E} \(word1) found your review on \(word2) useful.

EDIT: see full tutorial here, for more info.

Answer 2

UILabel as a subclass of UIView has a variable named semanticContentAttribute which you can set to .foreRightToLeft, it can also be set from the nib inspector through the Semantic pop-up menu in the attributes inspector.

Moreover, you can query effectiveUserInterfaceLayoutDirection property for debugging it's state.

See this for reference.

Now if you need both alignments in one label it will be tricky, either group two labels in a container UIView or see if you can set these values for portions of an NSMutableAttributedString which you can feed to a UILabel.

The textAlignment properties you are trying to set will give you the same effect that MS-Word does to paragraph alignment but wouldn't flip reading direction for language.

Happy coding!

Edit: This is an example of what I am suggesting with attributed strings although when changing the arabic setting to RightToLeft it puts it at the bottom of the string... Maybe the flags need to be combined differently?

override func viewDidLoad() {
    super.viewDidLoad()
    let label = UILabel()

    let myMutableString = NSMutableAttributedString()

    //right-to-left
    let multipleAttributes: [String : AnyObject] = [
        NSForegroundColorAttributeName: UIColor.orangeColor(),
        NSBackgroundColorAttributeName: UIColor.blueColor(),
        NSUnderlineStyleAttributeName: NSUnderlineStyle.StyleDouble.rawValue,
        NSWritingDirectionAttributeName : [NSWritingDirection.LeftToRight.rawValue ]
    ]

    let myAttrString = NSAttributedString(string: "عبد الله", attributes: multipleAttributes)

    myMutableString.appendAttributedString(myAttrString)

    //some-text

    let someText = NSAttributedString(string: " finds ", attributes: nil)

    myMutableString.appendAttributedString(someText)

    //left-to-right
    let multipleAttributes2: [String : AnyObject] = [
        NSForegroundColorAttributeName: UIColor.blueColor(),
        NSBackgroundColorAttributeName: UIColor.yellowColor(),
        NSUnderlineStyleAttributeName: NSUnderlineStyle.StyleDouble.rawValue,
        NSWritingDirectionAttributeName : [NSWritingDirection.LeftToRight.rawValue | NSTextWritingDirection.Embedding.rawValue]
    ]

    let myAttrString2 = NSAttributedString(string: "restaurant", attributes: multipleAttributes2)

    myMutableString.appendAttributedString(myAttrString2)

    label.attributedText = myMutableString

    self.view.addSubview(label)
    label.sizeToFit()
    label.center = self.view.center

}