Storing custom alloc'ed objects in an array. Memory Management

Question

I am not sure if I am writing this code correctly.

Fruit * o1 = [[Fruit alloc] initWithName:kFruitOrange imageView:orange1] ;
fruitArray = [[NSMutableArray arrayWithObjects:o1, nil] retain]; // retain array for later use.

There are actually several fruits. Since I alloc them, then assign them to an array in my class init method. When and how should I release these objects.

CLARIFICATION. If I release [o1 release] after saving in array, I get "exc_bad_access" errors when looking at the array in other methods.

In my viewDidUnload method, I have gone through the array and released each object manually.

  for (Fruit * f  in fruitArray) {
        [f release];
    }

I have never seen anyone else do this in code before, so I am thinking that this is not the correct way to do it?

UPDATE

-(Fruit *) initWithName:(enum fruitTypes)fruitName imageView:(UIImageView *)iv{
    if((self = [super init])){
        name = @"Fuit Object";
        NSLog(@"creating orange colour %i", fruitName);
        switch (fruitName) {
            case kFruitOrange:
                 NSLog(@"creating orange colour ");
                colour = [UIColor orangeColor] ;
                break;
            case kFruitBanana:
                colour = [UIColor yellowColor];
                break;
            case kFruitKiwi:
                colour = [UIColor greenColor];
                break;
            case kFruitBlue:
                colour = [UIColor blueColor];
                break;
            default:
                NSLog(@"COLOUR NOT FOUND");
                break;
        }
        value = fruitName;
        imageView = iv;
        center = iv.center;


        [colour retain];
        [imageView retain];
        [name retain];


        return self;
    }
    return nil;

}

** ANSWER WAS I NEEDED TO RETAIN THE VARIABLES I SET IN MY FRUIT.M CLASS.

Take that for() loop out of your viewDidUnload method. It is absolutely wrong to manage your memory like that. — Dave DeLong
– Dave DeLong, Commented May 2, 2011 at 23:34
IT LOOKS TO BE SOMEWHERE ELSE IN MY CODE ; ( THANKS VLADIMIR, CORRECT ANSWER BELOW. — John Ballinger
– John Ballinger, Commented May 2, 2011 at 23:52

Vladimir · Accepted Answer · 2011-05-02 22:44:33Z

6

Release objects right after you add them to array - standard objective-c containers retain their elements and then release them when container itself is deallocated, so you don't need to worry about memory management yourself.

So when you create and fill your array release your elements:

Fruit * o1 = [[Fruit alloc] initWithName:kFruitOrange imageView:orange1] ;
fruitArray = [[NSMutableArray arrayWithObjects:o1, nil] retain];
[o1 release];

And in your viewDidUnload method (and in dealloc) just release your array, not its elements:

[fruitArray release];

The reason you get errors if you put [o1 release]; in your code is that in that case you release your object twice and it have been retain just once - when allocated.

edited May 2, 2011 at 22:44

answered May 2, 2011 at 22:32

Vladimir

171k36 gold badges392 silver badges313 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

Kal Over a year ago

I think the poster said that if he released it right after, he gets errors later in the code.

Dave DeLong Over a year ago

@Kal yep, but that's an indication that he's got errors elsewhere in his code. Vladimir's answer is correct.

John Ballinger Over a year ago

Hi Vladimir. I thought that was correct as well, and I still think that is correct. But when I release my Fruit object after adding it into the array, the fruit object does not seemed to be retained so when I access it later it causes "exc_bad_access". This is why I am a bit confused and added the unique release loop.

Vladimir Over a year ago

Does your actual code differ from what you posted? May be if do something different with multiple fruits... This approach should work fine

John Ballinger Over a year ago

You are correct. The issue is in my Fruit Class, When I do release after adding to array. I cannot access fruit.colour, I save this value in my Fruit.m file with colour = [[UIColour redColor] retain]; But now I cannot access fruitObject.colour later in code? I don't quite get why my colour object is not retained?

Collectives™ on Stack Overflow

Storing custom alloc'ed objects in an array. Memory Management

1 Answer 1

5 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

5 Comments

Your Answer

Sign up or log in

Post as a guest

Related