Change app language programmatically for Localization in iOS

Question

I am creating an iPhone application for five different countries. so, as per the country name, i have added Localizable.strings (refer to below screenshot-1) in app resource and it's working fine for me with device setting language changes.

[btnAIO setTitle:NSLocalizedString(@"AllInOnesTitle", nil) forState:UIControlStateNormal];

Now my app requirement has got changed, And i am getting user country code after login successfully. As per the requirement, user should not have to change the language from the device settings. So, very first time i need to display my login screen in English text only for all the users and after login successfully, as per the user country code i need to change all the text respectively for my app.

It is possible by giving five conditions (to check country language code) for all my texts, but this is not a correct way to do this.

Can anyone please suggest me which is the best way to do this? Thanks!

Answer 1

You can create category for NSBundle called it NSBundle+Language

NSBundle+Language.h

#import <Foundation/Foundation.h>

@interface NSBundle (Language)
+(void)setLanguage:(NSString*)language;
@end

NSBundle+Language.m

#import "NSBundle+Language.h"
#import <objc/runtime.h>

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, &_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(&onceToken, ^
                  {
                      object_setClass([NSBundle mainBundle],[BundleEx class]);
                  });
    objc_setAssociatedObject([NSBundle mainBundle], &_bundle, language ? [NSBundle bundleWithPath:[[NSBundle mainBundle] pathForResource:language ofType:@"lproj"]] : nil, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
@end

so you can set for every country code its language name then when select country call the method of setLanguage with the language

as example [NSBundle setLanguage:"en"];