Supporting right-to-left languages in iOS / Swift

Here is the list of techniques I use to make my iOS apps compatible with right-to-left languages.

1. By default Auto Layout will take care of the right-to-left layout when .Leading and .Trailing layout attributes are used.
2. Right-to-left layout can be tested by changing Application Language settings to Right to Left Pseudolanguage in the scheme Run settings (Product > Scheme > Edit Scheme…).
3. semanticContentAttribute property of a UIView can be used to change the default layout technique. For example, one can force the view to remain in the left-to-right mode. Same can be done in the Storyboard by changing the Semantic property of the Attributes Inspector.
4. In order to flip images for right-to-left users use imageFlippedForRightToLeftLayoutDirection() method of an UIImage object.
5. And finally, here is how to check if the view is currently displayed in the left-to-right mode:

let isLeftToRight = UIView.userInterfaceLayoutDirection(
      for: view.semanticContentAttribute) == .leftToRight

Reference

• New UIKit Support for International User Interfaces Video: WWDC 2015 video.

• About Internationalization and Localization: iOS Developer Library.

• Localizing text in Swift code.

• Localizing numbers, date, time and names in iOS / Swift