Question

I narrowed down my problem to not allocating memory properly. I have a NSMutableArray called subjects as a member of a Category. When I populate the category with the array of subjects it doesn’t store.

I am not sure how and where to allocate the memory for subjects, which is what I believe my problem is.

Here is the snippet:

    Category *cat = [[Category alloc] init];
    cat.category_title = [result_categories stringForColumn:@"CATEGORY"];

    QuotesAppDelegate *appDelegate = (QuotesAppDelegate *)[[UIApplication sharedApplication] delegate];

    for (Subject *sb in appDelegate.subjects){

        if([cat.category_title isEqualToString:sb.category_title]){
            [cat.subjects addObject:sb];
            NSLog(@"Adding subject: %@ cat.subjects.count=%i", sb.title, cat.subjects.count);

        }

    }

(The above log does print cat.subject names but it doesn’t print the subjects.count)

Answer 1

Have you allocate memory to cat.subjects like

cat.subject = [[NSMutableArray alloc] init];

or

subject = [[NSMutableArray alloc] init];

in your Category class ? if not then do it. This might be the one of the problem.

---

Update

first of all change your code from Category *cat = [Category alloc]; to Category *cat = [[Category alloc] init];

and change your init as

- (id)init {
    self = [super init];
    if (self) {
        subjects = [[NSMutableArray alloc] init]; 
    }
    return self;
}