How to force NSLocalizedString to use a specific language

Question

On iPhone NSLocalizedString returns the string in the language of the iPhone  Is it possible to force NSLocalizedString to use a specific language to have the app in a different language than the device

User · Answer

I came up with a solution that allows you to use NSLocalizedString. I create a category of NSBundle call NSBundle+RunTimeLanguage. The interface is like this.

// NSBundle+RunTimeLanguage.h
#import <Foundation/Foundation.h>
@interface NSBundle (RunTimeLanguage)
#define NSLocalizedString(key, comment) [[NSBundle mainBundle] runTimeLocalizedStringForKey:(key) value:@"" table:nil]
- (NSString *)runTimeLocalizedStringForKey:(NSString *)key value:(NSString *)value table:(NSString *)tableName;
@end

The implementation is like this.

// NSBundle+RunTimeLanguage.m
#import "NSBundle+RunTimeLanguage.h"
#import "AppDelegate.h"

@implementation NSBundle (RunTimeLanguage)

- (NSString *)runTimeLocalizedStringForKey:(NSString *)key value:(NSString *)value table:(NSString *)tableName
{
    AppDelegate *appDelegate = (AppDelegate *)[UIApplication sharedApplication].delegate;
    NSString *path= [[NSBundle mainBundle] pathForResource:[appDelegate languageCode] ofType:@"lproj"];
    NSBundle *languageBundle = [NSBundle bundleWithPath:path];
    NSString *localizedString=[languageBundle localizedStringForKey:key value:key table:nil];
    return localizedString;
}
@end

Than just add import NSBundle+RunTimeLanguage.h into the files that use NSLocalizedString.

As you can see I store my languageCode in a property of AppDelegate. This could be stored anywhere you'd like.

This only thing I don't like about it is a Warning that NSLocalizedString marco redefined. Perhaps someone could help me fix this part.

User · Answer

Based on Tudorizer s answer to change language without leaving or restarting the application    Instead of a macro  use a class for accessing the preferred language in order to check if a specific language code is present   Below is a class used to obtain the current language bundle that is working for iOS 9    implementation OSLocalization     NSBundle   currentLanguageBundle          Default language incase an unsupported language is found     NSString  language     en        if   NSLocale preferredLanguages  count               Check first object to be of type  en   es  etc            Codes seen by my eyes   en-US   en   es-US   es  etc          NSString  letterCode     NSLocale preferredLanguages  objectAtIndex 0            if   letterCode rangeOfString   en   location    NSNotFound                   English             language     en             else if   letterCode rangeOfString   es   location    NSNotFound                   Spanish             language     es             else if   letterCode rangeOfString   fr   location    NSNotFound                   French             language     fr                Add more if needed            return  NSBundle bundleWithPath   NSBundle mainBundle  pathForResource language ofType   lproj            Check if preferred language is English    BOOL isCurrentLanguageEnglish       if    NSLocale preferredLanguages  count               Just incase check for no items in array         return YES             if     NSLocale preferredLanguages  objectAtIndex 0  rangeOfString   en   location    NSNotFound               No letter code for english found         return NO        else              Tis English         return YES               Swap language between English  amp  Spanish     Could send a string argument to directly pass the new language        void changeCurrentLanguage       if   self isCurrentLanguageEnglish               NSUserDefaults standardUserDefaults  setObject     es   forKey   AppleLanguages          else             NSUserDefaults standardUserDefaults  setObject     en   forKey   AppleLanguages             end   Use the class above to reference a string file   image   video   etc      Access a localized image   OSLocalization currentLanguageBundle  pathForResource   my image name png  ofType nil     Access  a localized string from Localizable strings file NSLocalizedStringFromTableInBundle   StringKey   nil   OSLocalization currentLanguageBundle     comment     Change language in-line like below or update the  changeCurrentLanguage  method in the class above to take a string parameter referencing the new language     NSUserDefaults standardUserDefaults  setObject     es   forKey   AppleLanguages

User · Answer

Swift Version   NSUserDefaults standardUserDefaults   setObject   fr    forKey   AppleLanguages   NSUserDefaults standardUserDefaults   synchronize

User · Answer

for my case i have two localized file   ja and en   and i would like to force it to en if the preferred language in the system neither en or ja  i m going to edit the main m file  i  ll check whether the first preferred is en or ja   if not then i  ll change the second preferred language to  en   int main int argc  char  argv             NSUserDefaults standardUserDefaults  removeObjectForKey   AppleLanguages          NSUserDefaults standardUserDefaults  synchronize        NSString  lang     NSLocale preferredLanguages  objectAtIndex 0        if    lang isEqualToString   en     amp  amp     lang isEqualToString   ja              NSMutableArray  array     NSMutableArray alloc  initWithArray  NSLocale preferredLanguages             array replaceObjectAtIndex 1 withObject   en               NSUserDefaults standardUserDefaults  setObject array forKey   AppleLanguages              NSUserDefaults standardUserDefaults  synchronize                 autoreleasepool           return UIApplicationMain argc  argv  nil  NSStringFromClass  AppDelegate class

User · Answer

For Swift you can override the main swift file and set the UserDefaults string there before you app runs  This way you do not have to restart the App to see the desired effect   import Foundation import UIKit     Your initialisation code here let langCultureCode  String    LANGUAGE CODE   UserDefaults standard set  langCultureCode   forKey   AppleLanguages   UserDefaults standard synchronize    UIApplicationMain CommandLine argc  CommandLine unsafeArgv  nil  NSStringFromClass AppDelegate self     paired together with the removal of  UIApplicationMain in your AppDelegate swift file

User · Answer

As said earlier  just do     NSUserDefaults standardUserDefaults  setObject   NSArray arrayWithObjects   el   nil  forKey   AppleLanguages      But to avoid having to restart the app  put the line in the main method of main m  just before UIApplicationMain

User · Answer

As Brian Webster mentions  the language needs to be set  sometime early in your application s startup   I thought applicationDidFinishLaunching  of the AppDelegate should be a suitable place to do it  since it s where I do all other initialization   But as William Denniss mentions  that seems to have an effect only after the app is restarted  which is kind of useless   It seems to work fine if I put the code in the main function  though   int main int argc  char  argv          NSAutoreleasePool   pool     NSAutoreleasePool alloc  init           Force language to Swedish        NSUserDefaults standardUserDefaults       setObject  NSArray arrayWithObject   sv        forKey   AppleLanguages         int retVal   UIApplicationMain argc  argv  nil  nil        pool release       return retVal      I d appreciate any comments on this

User · Answer

NSLocalizedString    and variants thereof  access the  AppleLanguages  key in NSUserDefaults to determine what the user s settings for preferred languages are   This returns an array of language codes  with the first one being the one set by the user for their phone  and the subsequent ones used as fallbacks if a resource is not available in the preferred language    on the desktop  the user can specify multiple languages with a custom ordering in System Preferences   You can override the global setting for your own application if you wish by using the setObject forKey  method to set your own language list   This will take precedence over the globally set value and be returned to any code in your application that is performing localization   The code for this would look something like     NSUserDefaults standardUserDefaults  setObject  NSArray arrayWithObjects   de     en     fr   nil  forKey   AppleLanguages      NSUserDefaults standardUserDefaults  synchronize     to make the change immediate   This would make German the preferred language for your application  with English and French as fallbacks   You would want to call this sometime early in your application s startup   You can read more about language locale preferences here  Internationalization Programming Topics  Getting the Current Language and Locale

User · Answer

whatever you all do  the best way is to take the short name for the specified language  i e   fr  en  nl  de  it  etc    and assign the same to a global value   make a picker view to pop up like a drop down menu  combination of a button on click of which a picker view appears from below with a list of languages  and select the language you desire  let the short name be stored internally  make a  h    m file named LocalisedString   Set the global value of short name to be equal to the obtained value in LocalisedString m When the required language is selected assign the NSBundlePath to create project sub-directories for the needed language  for eg  nl proj  en proj   When the particular proj folder is selected call the localised string for the respective language and change the language dynamically   no rules broken

User · Answer

Here is a decent solution for this problem  and it does not require application restart   https   github com cmaftuleac BundleLocalization  This implementation works by tweaking inside NSBundle  The idea is that you override the method localizedStringForKey on the instance of NSBundle object  and then call this method on a different bundle with a different language  Simple and elegant fully compatible with all types of resources

User · Answer

Do not use on iOS 9   This returns nil for all strings passed through it   I have found another solution that allows you to update the language strings  w o restarting the app and compatible with genstrings   Put this macro in the Prefix pch    define currentLanguageBundle  NSBundle bundleWithPath   NSBundle mainBundle  pathForResource   NSLocale preferredLanguages  objectAtIndex 0  ofType   lproj      and where ever you need a localized string use    NSLocalizedStringFromTableInBundle   GalleryTitleKey   nil  currentLanguageBundle         To set the language use     NSUserDefaults standardUserDefaults  setObject  NSArray arrayWithObject   de   forKey   AppleLanguages      Works even with consecutive language hopping like   NSLog   test      NSLocalizedStringFromTableInBundle   NewKey   nil  currentLanguageBundle           NSUserDefaults standardUserDefaults  setObject  NSArray arrayWithObject   fr   forKey   AppleLanguages    NSLog   test      NSLocalizedStringFromTableInBundle   NewKey   nil  currentLanguageBundle           NSUserDefaults standardUserDefaults  setObject  NSArray arrayWithObject   it   forKey   AppleLanguages    NSLog   test      NSLocalizedStringFromTableInBundle   NewKey   nil  currentLanguageBundle           NSUserDefaults standardUserDefaults  setObject  NSArray arrayWithObject   de   forKey   AppleLanguages    NSLog   test      NSLocalizedStringFromTableInBundle   NewKey   nil  currentLanguageBundle

User · Answer

I had the same problem recently and I didn t want to start and patch my entire NSLocalizedString nor force the app to restart for the new language to work  I wanted everything to work as-is   My solution was to dynamically change the main bundle s class and load the appropriate bundle there   Header file   interface NSBundle  Language    void setLanguage  NSString  language   end   Implementation   import  lt objc runtime h gt   static const char  bundle 0    interface BundleEx   NSBundle  end   implementation BundleEx - NSString  localizedStringForKey  NSString   key value  NSString   value table  NSString   tableName       NSBundle  bundle objc getAssociatedObject self   amp  bundle       return bundle    bundle localizedStringForKey key value value table tableName     super localizedStringForKey key value value table tableName      end   implementation NSBundle  Language    void setLanguage  NSString  language       static dispatch once t onceToken      dispatch once  amp onceToken                  object setClass  NSBundle mainBundle   BundleEx class                objc setAssociatedObject  NSBundle mainBundle    amp  bundle  language    NSBundle bundleWithPath   NSBundle mainBundle  pathForResource language ofType   lproj      nil  OBJC ASSOCIATION RETAIN NONATOMIC      end   So basically  when your app starts and before you load your first controller  simply call    NSBundle setLanguage   en      When your user changes his preferred language in your setting screen  simply call it again    NSBundle setLanguage   fr      To reset back to system defaults  simply pass nil    NSBundle setLanguage nil     Enjoy     For those who need a Swift version    var bundleKey  UInt8   0  class AnyLanguageBundle  Bundle        override func localizedString forKey key  String                                    value  String                                     table tableName  String   - gt  String            guard let path   objc getAssociatedObject self   amp bundleKey  as  String                let bundle   Bundle path  path  else                return super localizedString forKey  key  value  value  table  tableName                         return bundle localizedString forKey  key  value  value  table  tableName           extension Bundle        class func setLanguage   language  String             defer                object setClass Bundle main  AnyLanguageBundle self                     objc setAssociatedObject Bundle main   amp bundleKey     Bundle main path forResource  language  ofType   lproj     OBJC ASSOCIATION RETAIN NONATOMIC

User · Answer

NSLocalizedString   reads the value for the key AppleLanguages from the standard user defaults   NSUserDefaults standardUserDefaults    It uses that value to choose an appropriate localization among all existing localizations at runtime  When Apple builds the user defaults dictionary at app launch  they look up the preferred language s  key in the system preferences and copy the value from there  This also explains for example why changing the language settings in OS X has no effect on running apps  only on apps started thereafter  Once copied  the value is not updated just because the settings change  That s why iOS restarts all apps if you change then language   However  all values of the user defaults dictionary can be overwritten by command line arguments  See NSUserDefaults documentation on the NSArgumentDomain  This even includes those values that are loaded from the app preferences   plist  file  This is really good to know if you want to change a value just once for testing   So if you want to change the language just for testing  you probably don t want to alter your code  if you forget to remove this code later on       instead tell Xcode to start your app with a command line parameters  e g  use Spanish localization      No need to touch your code at all  Just create different schemes for different languages and you can quickly start the app once in one language and once in another one by just switching the scheme

User · Answer

What do you think about this solution for Swift 3   extension String        func localized forLanguage language  String   Locale preferredLanguages first  components separatedBy   -   first   - gt  String            guard let path   Bundle main path forResource  language     en     Base    language  ofType   lproj   else                let basePath   Bundle main path forResource   Base   ofType   lproj                 return Bundle path  basePath   localizedString forKey  self  value      table  nil                     return Bundle path  path   localizedString forKey  self  value      table  nil            Simple usage    report  localized forLanguage   pl     forced language  report  localized     default language selected by user in settings  in case when your app doesnt support selected lanaguage  the default one is selected  here is an english

User · Answer

In file  pch to define        define currentLanguageBundle  NSBundle bundleWithPath   NSBundle mainBundle  pathForResource   NSLocale preferredLanguages  objectAtIndex 0  ofType   lproj       define NSLocalizedString str nil  NSLocalizedStringFromTableInBundle str  nil  currentLanguageBundle

User · Answer

Swift 3 solution   let languages     bs    zh-Hant    en    fi    ko    lv    ms    pl    pt-BR    ru    sr-Latn    sk    es    tr   UserDefaults standard set  languages 0    forKey   AppleLanguages     Gave some examples of language codes that can be used  Hope this helps

User · Answer

I like best Mauro Delrio s method  I also have added the following in my Project Prefix pch   import  Language h       define MyLocalizedString key  alt   Language get key alter alt    So if you ever want to use the standard method  that uses NSLocalizedString  you can make a quick syntax substitution in all files

User · Answer

You could build a sub-bundle with the set of localized strings that you want to do this with  and then use NSLocalizedStringFromTableInBundle   to load them   I m assuming that this is content separate from the normal UI localization you might be doing on the app

User · Answer

In swift 4  I have solved it without needing to restart or use libraries   After trying many options  I found this function  where you pass the  stringToLocalize   of Localizable String  the strings file  that you want to translate  and the  language  in which you want to translate it  and what it returns is the value for that String that you have in Strings file           func localizeString  stringToLocalize  String  language  String  - gt  String                           let path   Bundle main path  forResource  language  ofType   lproj                   let languageBundle   Bundle  path  path                   return languageBundle   localizedString  forKey  stringToLocalize  value      table  nil              Taking into account this function  I created this function in a Swift file   struct CustomLanguage        func createBundlePath    - gt  Bundle           let selectedLanguage     recover the language chosen by the user  in my case  from UserDefaults          let path   Bundle main path forResource  selectedLanguage  ofType   lproj           return Bundle path  path              To access from the whole app  and in each string of the rest of ViewControllers  instead of putting   NSLocalizedString   StringToLocalize   comment          I have replaced it with  let customLang   CustomLanguage     declare at top let bundleLanguage   customLang createBundle    NSLocalizedString  StringToLocalize   tableName  nil  bundle  bundleLanguage  value      comment            use in each String   I do not know if it s the best way  but I found it very simple  and it works for me  I hope it helps you

User · Answer

Maybe you should complement with this  on  pch file after  import     extern NSBundle  bundle     Declared on Language m   ifdef NSLocalizedString      undef NSLocalizedString        Delete this line to avoid warning      warning  Undefining NSLocalizedString   endif   define NSLocalizedString key  comment         bundle localizedStringForKey  key  value     table nil

User · Answer

The trick to use specific language by selecting it from the app is to force the NSLocalizedString to use specific bundle depending on the selected language    here is the post i have written for this  learning advance localization in ios apps  and here is the code of one sample app advance localization in ios apps

User · Answer

In a nutshell    Localize your application  It s the first thing you have to do is to localise your app with at least two languages  english and french in this example    Override NSLocalizedString  In your code  instead of using NSLocalizedString key  comment   use a macro MYLocalizedString key  comment  defined like this    define MYLocalizedString key  comment    MYLocalizationSystem sharedInstance  localizedStringForKey  key  value  comment     This MYLocalizationSystem singleton will     Set langage by setting the right localized NSBundle user asks for Returns the localized NSString according to this previously set language   Set user language  When user changed application language in french  call   MYLocalizationSystem sharedInstance  setLanguage   fr     -  void setLanguage  NSString   lang       NSString  path     NSBundle mainBundle  pathForResource lang ofType   lproj        if   path                 bundle    NSBundle mainBundle           NSLog   Warning  No lproj for     system default set instead     lang           return              bundle    NSBundle bundleWithPath path       In this example this method set localized bundle to fr lproj  Return localized string  Once you ve set the localized bundle  you ll be able to get the right localised string from him with this method    -  NSString   localizedStringForKey  NSString   key value  NSString   value          bundle was initialized with  NSBundle mainBundle  as default and modified in setLanguage method     return  self bundle localizedStringForKey key value value table nil       Hope this will help you   You ll find more details in this article from NSWinery io

User · Answer

You can do something like this   NSString  bundlePath     NSBundle mainBundle  pathForResource   Localizable  ofType   strings  inDirectory nil forLocalization   es      NSBundle  spanishBundle     NSBundle alloc  initWithPath  bundlePath stringByDeletingLastPathComponent     NSLocalizedStringFromTableInBundle   House   nil  spanishBundle  nil

User · Answer

This function will try to get localized string for current language and if it s not found it will get it using english language   -  NSString  L  NSString  key       static NSString  valueNotFound     VALUE NOT FOUND       static NSBundle  enBundle   nil       NSString  pl    NSLocale preferredLanguages  0       NSString  bp     NSBundle mainBundle  pathForResource pl ofType   lproj        NSBundle  b    NSBundle bundleWithPath bp        NSString  s    b localizedStringForKey key value valueNotFound table nil       if    s isEqualToString valueNotFound              if    enBundle                 bp     NSBundle mainBundle  pathForResource   en  ofType   lproj                enBundle    NSBundle bundleWithPath bp                     s    enBundle localizedStringForKey key value key table nil              return s

User · Answer

I usually do this in this way  but  you MUST have all localization files in your project    implementation Language  static NSBundle  bundle   nil     void initialize        NSUserDefaults  defs    NSUserDefaults standardUserDefaults       NSArray  languages    defs objectForKey   AppleLanguages        NSString  current     languages objectAtIndex 0  retain        self setLanguage current           example calls       Language setLanguage   it         Language setLanguage   de         void setLanguage  NSString   l       NSLog   preferredLang       l       NSString  path      NSBundle mainBundle   pathForResource l ofType   lproj         bundle     NSBundle bundleWithPath path  retain        NSString   get  NSString   key alter  NSString   alternate        return  bundle localizedStringForKey key value alternate table nil       end

User · Answer

Swift 3 extensions   extension Locale       static var preferredLanguage  String           get               return self preferredLanguages first     en                    set               UserDefaults standard set  newValue   forKey   AppleLanguages               UserDefaults standard synchronize                      extension String       var localized  String        var result  String      let languageCode   Locale preferredLanguage   en-US      var path   Bundle main path forResource  languageCode  ofType   lproj        if path    nil  let hyphenRange   languageCode range of   -             let languageCodeShort   languageCode substring to  hyphenRange lowerBound     en         path   Bundle main path forResource  languageCodeShort  ofType   lproj              if let path   path  let locBundle   Bundle path  path            result   locBundle localizedString forKey  self  value  nil  table  nil        else           result   NSLocalizedString self  comment                    return result           Usage   Locale preferredLanguage    uk   label text    localizedKey  localized

User · Answer

I wanted to add support for a language that isn t officially supported by iOS  not listed in Language section under system settings   By following the Apple s Internationalization Tutorial and few hints here by Brian Webster and geon  I came up with this piece of code  put it in main m    int main int argc  char   argv           autoreleasepool              Grab regional settings locale  for Slovenian this is either sl SI or en SI         NSLocale  locale    NSLocale currentLocale           NSString  ll    locale localeIdentifier      sl SI             Grab the first part of language identifier         NSArray  comp    ll componentsSeparatedByString                NSString  ll1     en           if  comp count  gt  0                ll1   comp 0      sl  en                           Check if we already saved language  user can manually change it inside app for example          if     NSUserDefaults standardUserDefaults  objectForKey   SelectedLanguage                       Slovenian  Slovenia              Slovenia             if   ll isEqualToString   sl SI       ll isEqualToString   en SI                      ll1     sl-SI      This is the part of localized path for Slovenian language that Xcode generates                              Add more unsupported languages here                   NSUserDefaults standardUserDefaults  setObject ll1 forKey   SelectedLanguage       Save language                   else                  Restore language as we have previously saved it             ll1     NSUserDefaults standardUserDefaults  objectForKey   SelectedLanguage                         Overwrite NSLocalizedString and StoryBoard language preference           NSUserDefaults standardUserDefaults  setObject  NSArray arrayWithObjects ll1    en     fr   nil  forKey   AppleLanguages               Make sure settings are stored to disk           NSUserDefaults standardUserDefaults  synchronize            return UIApplicationMain argc  argv  nil  NSStringFromClass  AppDelegate class               This works well for both Storyboard and NSLocalizedString code  The code assumes that user will have an option to manually change language inside app later on   Of course  don t forget to add proper Storyboard translations and Localizable strings translations  see link to Apple page above for how to do that

[ios] How to force NSLocalizedString to use a specific language

Examples related to ios

Examples related to objective-c

Examples related to localization

Examples related to internationalization

Examples related to nslocalizedstring