iOS: Determine if device language is Right to Left (RTL)

Question

Is there a way to easily determine if the language the device is set to is right to left (RTL)?

Answer 1

Ok, although it's an old question with an accepted answer, I will answer it anyway.

For those who wants to check whether the device language is RTL, independent if your application supports or not this language, you should use [NSLocale characterDirectionForLanguage:] like this:

+ (BOOL)isDeviceLanguageRightToLeft {

    NSLocale *currentLocale = [NSLocale currentLocale];
    NSLocaleLanguageDirection direction = [NSLocale characterDirectionForLanguage:[currentLocale objectForKey:NSLocaleLanguageCode]];
    return (direction == NSLocaleLanguageDirectionRightToLeft);
}

The code above will return YES if your app only supports english, but your device is set to Arabic for example.

Apple recommends that you use [UIApplication sharedApplication].userInterfaceLayoutDirection, just because it returns the direction based on the language that your app is using (has support to). Here is the code snippet:

+ (BOOL)isAppLanguageRightToLeft {

    NSLocaleLanguageDirection direction = [UIApplication sharedApplication].userInterfaceLayoutDirection;
    return (direction == UIUserInterfaceLayoutDirectionRightToLeft);
}

The code above will return NO when your app only supports english, but your device is set to Arabic for example.