(iOS) NSUserDefaults

1.setFlag.mm

//Set the (bool) flag
[[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"logged_in"];
[[NSUserDefaults standardUserDefaults]synchronize];

//Read it
if(![[NSUserDefaults standardUserDefaults] boolForKey:@"logged_in"]) 
{
    [self displayLogin];
} else {
    [self displayMainScreen];
}

2.example.mm

-(void)saveToUserDefaults:(NSString*)myString
{
  NSUserDefaults *standardUserDefaults = [NSUserDefaults standardUserDefaults];

	if (standardUserDefaults) {
		[standardUserDefaults setObject:myString forKey:@"Prefs"];
		[standardUserDefaults synchronize];
	}
}

-(NSString*)retrieveFromUserDefaults
{
	NSUserDefaults *standardUserDefaults = [NSUserDefaults standardUserDefaults];
	NSString *val = nil;
	
	if (standardUserDefaults) 
		val = [standardUserDefaults objectForKey:@"Prefs"];
	
	return val;
}

3.favorites.mm

+(void) addToFavorites: (Record *)record {
    if (!Eng.user.loggedIn) return;
    
    NSString *key = [[NSString alloc] initWithFormat:@"%@%i", STORE_DATA_FAVORITES_KEY, Eng.user.userId];
    
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    
    NSMutableArray *favorites = [[(NSMutableArray *)[defaults objectForKey:key] mutableCopy] autorelease];
    
    if (favorites == nil) {
        favorites = [NSMutableArray array];
    }
    
    NSData *encodedObject = [NSKeyedArchiver archivedDataWithRootObject:record];
    
    if (![favorites containsObject:encodedObject])
        [favorites addObject:encodedObject];
    
    [defaults setObject:favorites forKey:key];
    [defaults synchronize];

    NSLog(@"Favorites: %i", favorites.count);
    
    [key release];
}


+(void) removeFromFavorites: (Record *)record {
    if (!Eng.user.loggedIn) return;
    NSString *key = [[NSString alloc] initWithFormat:@"%@%i", STORE_DATA_FAVORITES_KEY, Eng.user.userId];
    
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    
    NSMutableArray *favorites = [[(NSMutableArray *)[defaults objectForKey:key] mutableCopy] autorelease];
    
    NSData *encodedObject = [NSKeyedArchiver archivedDataWithRootObject:record];
    
    [favorites removeObject:encodedObject];
    
    [defaults setObject:favorites forKey:key];
    [defaults synchronize];
    
    NSLog(@"Favorites: %i", favorites.count);
    
    [key release];
}



+(NSInteger) countFavorites {
    if (!Eng.user.loggedIn) return 0;
    NSString *key = [[NSString alloc] initWithFormat:@"%@%i", STORE_DATA_FAVORITES_KEY, Eng.user.userId];
    
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    
    NSMutableArray *favorites = [defaults objectForKey:key];
    
    [key release];
    
    return favorites.count;
}



+(NSArray *) getFavoritesAsRecords {
    if (!Eng.user.loggedIn) return nil;
    NSString *key = [[NSString alloc] initWithFormat:@"%@%i", STORE_DATA_FAVORITES_KEY, Eng.user.userId];
    
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    
    NSMutableArray *favorites = [defaults objectForKey:key];
    
    //Used to reset favorites
//    [defaults setObject:[NSMutableArray array] forKey:key];
//    [defaults synchronize];
    
    NSMutableArray *favs = [[NSMutableArray alloc] init];
    
    NSEnumerator *e = [favorites objectEnumerator];
    NSData *object;
    Record *record;
    while (object = [e nextObject]) {
        record = (Record *)[NSKeyedUnarchiver unarchiveObjectWithData:(NSData *)object];
        [favs addObject:record];
    }
    
    MyLog(@"Will show %i records", favs.count);
    
    [key release];
    
    return [favs autorelease];
}



+(BOOL) isInFavorites: (Record *)record {
    if (!Eng.user.loggedIn) return NO;
    NSString *key = [[NSString alloc] initWithFormat:@"%@%i", STORE_DATA_FAVORITES_KEY, Eng.user.userId];
    
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    
    NSMutableArray *favorites = [defaults objectForKey:key];
    
    NSData *encodedObject = [NSKeyedArchiver archivedDataWithRootObject:record];
    
    [key release];
    
    return [favorites containsObject:encodedObject];
}

4.NSUserDefaultsUsage.mm

//Usage

NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];

//Setting values
– setBool:forKey:
– setFloat:forKey:
– setInteger:forKey:
– setObject:forKey:
– setDouble:forKey:
– setURL:forKey:

//Getting values
– boolForKey:
– floatForKey:
– integerForKey:
– objectForKey:
– doubleForKey:
– URLForKey:

//Remove an object
[[NSUserDefaults standardUserDefaults] removeObjectForKey:@"MyKey"];