What's the best way to store many NSDictionaries?

Question

I need to store many Facebook App Id's and Twitter Consumer Keys for differente configurations and settings in my iPhone application.

I know the way I'm doing this is not the best one, because it has too many if else statements. What would be the best way to accomplish this task, using a correct Objective-C design pattern?

Here is my code:

- (id) init {
self = [super init];
if (!self) return nil;

keyNames = [[NSArray arrayWithObjects:
             @"facebookAppId", 
             @"facebookLocalAppId",
             @"twitterConsumerKey",
             @"twitterSecret",
             nil]retain];

if (MainLanguage == @"English") {

    keys = [[NSArray arrayWithObjects:
             @"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", //facebookAppId
             @"yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy", //facebookLocalAppId
             @"zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz", //twitterConsumerKey
             @"wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww", //twitterSecret
             nil]retain];

    dictionary = [[NSDictionary dictionaryWithObjects:keys forKeys:keyNames]retain];

}

else if (MainLanguage == @"Spanish") {

    keys = [[NSArray arrayWithObjects:
             @"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa", //facebookAppId
             @"bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb", //facebookLocalAppId
             @"cccccccccccccccccccccccccccccccc", //twitterConsumerKey
             @"dddddddddddddddddddddddddddddddd", //twitterSecret
             nil]retain];

    dictionary = [[NSDictionary dictionaryWithObjects:keys forKeys:keyNames]retain];

}  else if (MainLanguage == @"French") {

   //etc...

} else if (MainLanguage == @"Italian") {

    //etc...

}


//etc..

return self;

}

-(void)dealloc {

    [keyNames release];
    [keys release];
    [dictionary release];
    [super dealloc];

}

Answer 1

Two main problems:

• Why are the key names in an array?
• You should not be comparing NSString*s with ==.

You also probably want to be using language codes.

I can think of two "Objective-C" options, one hacky option, and one "C" option:

1. Store it in a dictionary. This seems a little wasteful because it constructs a bunch of dictionaries and only uses one of them.

   [NSDictionary dictionaryWithObjectsAndKeys:
     [NSDictionary dictionaryWithObjectsAndKeys:
       @"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", @"facebookAppId",
       @"yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy", @"facebookLocalAppId",
       ...
     nil], @"en",
     [NSDictionary dictionaryWithObjectsAndKeys:
       @"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa", @"facebookAppId",
       ...
     nil], @"es",
     ...
   nil]
   

2. Stick it a dictionary in a plist. This might be problematic, because all someone has to do to extract them is unzip your .ipa.

   <dict>
     <key>en</key>
     <dict>
       <key>facebookAppId</key>
       <string>...</string>
       ...
     </dict>
     <key>es</key>
     <dict>
       ...
     </dict>
     ...
   </dict>
   

3. Store it in Localizable.strings. Again, trivial to extract by unzipping the .ipa.

4. Store it in an array of structs:

   struct {
     NSString *lang;
     NSString *facebookAppId;
     NSString *facebookLocalAppId;
     NSString *twitterConsumerKey;
     NSString *twitterConsumerSecret;
   } const foo_data[] = {
     {@"en", @"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", @"yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy", ...},
     {@"es", @"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa", ...},
     ...
   };
   
   ...
   
   for (size_t i = 0; i < sizeof(foo_data)/sizeof(foo_data[0]); i++) {
     if ([lang isEqualToString:foo_data[i].lang]) {
       return [NSDictionary dictionaryWithObjectsAndKeys:
                foo_data[i].facebookAppId,@"facebookAppId",
                ...
              nil];
     }
   }
   

Answer 2

Well the data has to be stored somewhere right? You could have a separate class that stores the data in a hash table. Then you just need to reference that able each time you get a language. Your code will definitely look cleaner. Check out NSHashTable.