Access the contents of an NSMutableArray between classes

I have an NSMutableArray in one of my classes. But I need to access the information contained within that array from another class. I have tried using properties, but I eithor did it wrong, or its not working for me. I tried NSUserDefaults but also no luck. I tried using

MainGame *mainGameClass = [[MainGame alloc]init];

NSMutableArray *snacksLocationArray = main.snacksArray;

but none of this seems to work. The two classes are n开发者_开发问答amed: MainGame and Kool

Thanks in advance.

If you provide access to your array then anyone should be able to access it. Using a singleton is more like making it a global variable than just allowing access to it.

// In MainGame.h
@interface MainGame : NSOBject {
    NSMutableArray *snacksLocationArray;
}
@property (retain) NSMutableArray *snacksLocationArray;
@end

// In MainGame.m
@implementation MainGame
@synthesize snacksLocationArray;
@end

// In Kool.h
@interface Kool : NSObject {
}
- (void) doSomethingFunkyWithSnacksArray: (NSMutatableArray *) a;
- (void) doSomethingWeirdWithMainGame: (MainGame *) g;
@end

// In Kool.m
@implementation Kool
- (void) doSomethingFunkyWithSnacksArray: (NSMutatableArray *) a {
    [a addObject: @"Funky"];
}
- (void) doSomethingWeirdWithMainGame: (MainGame *) g {
    [self doSomethingFunkyWithSnacksArray: g.snacksLocationArray];
    [g.snacksLocationArray addObject: @"Weird"];
}

Does this do what you are thinking? Lets you access the array from methods in Kool. "Funky" and "Weird" will be properly stored in the array for use within MainGame.

You could also set an ivar to the array within Kool for access to the array using methods that may not have access to the MainGame object.

You could use a singleton, on which you have your mutablearray set as a property. So you could call something like [MainGame sharedGame].snacksArray from anywhere within your app.

Here's what your sharedGame method should look like:

static MainGame *sharedGame = nil;

+ (MainGame *)sharedGame {

    if(sharedGame == nil)
        sharedGame = [[super alloc] init];

    return sharedGame;
}