Macro for NSLocalizedString not working - ios

Question

I build a Macro for NSLocalizedString like this in my Prefix.pch:
#undef NSLocalizedString
#define NSLocalizedString(key,_comment) [[LocalizedText sharedInstance] localizedStringFor:key]
My LocalizedText class looks like this:
+ (LocalizedText *)sharedInstance {
#synchronized(self)
{
if (_singletonInstance == nil)
_singletonInstance = [[LocalizedText alloc] init];
}
return _singletonInstance;
}
- (NSString *) localizedStringFor:(NSString*) key
{
NSUserDefaults *deviceLanguage = [NSUserDefaults standardUserDefaults];
NSString *currentLanguage = [deviceLanguage objectForKey:#"deviceLanguage"];
NSString *path;
if([currentLanguage isEqual: #"en"])
path = [[NSBundle mainBundle] pathForResource:#"en" ofType:#"lproj"];
else if([currentLanguage isEqual: #"de"])
path = [[NSBundle mainBundle] pathForResource:#"de" ofType:#"lproj"];
else if([currentLanguage isEqual: #"it"])
path = [[NSBundle mainBundle] pathForResource:#"it" ofType:#"lproj"];
NSBundle* languageBundle = [NSBundle bundleWithPath:path];
NSString* str=[languageBundle localizedStringForKey:key value:#"" table:nil];
return str;
}
So for example, when i change my NSUserDefaults to #"en", i expect that every NSLocalizedString gives me the correct english translation, but it never changes and is always the default language. Whats wrong with my code?

Answer 1

Before debugging your Macro, I would set up a test as follows:
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *currentLanguage = [defaults objectForKey:#"deviceLanguage"];
NSString *key = #"SomeKeyFromYourLocalizedFile";
NSString *localized = [[LocalizedText sharedInstance] localizedStringFor:key];
NSLog(#"%#: %#", currentLanguage, localized);
[defaults setObject:#"de" forKey:#"deviceLanguage"];
[defaults synchronize];
NSString *localized = [[LocalizedText sharedInstance] localizedStringFor:key];
NSLog(#"%#: %#", currentLanguage, localized);
[defaults setObject:#"it" forKey:#"deviceLanguage"];
[defaults synchronize];
NSString *localized = [[LocalizedText sharedInstance] localizedStringFor:key];
NSLog(#"%#: %#", currentLanguage, localized);
And see the output of that. Your bug is probably somewhere in there.
I expect:
en: English localized
de: German localized
it: Italian localized
After that, you would simply use your macro (which looks like it will work just like that). I tried:
#ifdef NSLocalizedString
#undef NSLocalizedString
#endif
#define NSLocalizedString(key, comment) NSLog(#"Output %#, %#", key, comment)
NSLocalizedString(#"First", #"Second");
Which results in:
2017-01-12 14:31:31.501 App[49000:50650596] Output First, Second