Question

NSArray * ComicArray = [TCSDataBase fetchManagedObjectsForEntity:@"ComicDB" withPredicate:nil];
    [ComicArray retain];

    arrayOfComics = [NSMutableArray arrayWithArray:ComicArray];
    [[arrayOfComics valueForKey:@"Name"] sortUsingSelector:@selector(caseInsensitiveCompare:)];

    [ComicArray release];

Why are all the object in the arrayOfComics out of scope?

EDIT: I tried doing this:

NSArray * ComicArray = [TCSDataBase fetchManagedObjectsForEntity:@"ComicDB" withPredicate:predicate];
    arrayOfComics =[[NSMutableArray alloc] init];
    for (int i = 0; i < [ComicArray count]; i++) {
        [arrayOfComics addObject:[ComicArray objectAtIndex:i]];
    }

    [[arrayOfComics valueForKey:@"Name"] sortUsingSelector:@selector(caseInsensitiveCompare:)];

All the objects in arrayOfComics are still out of scope….

EDIT: This works, the objects in arrayOfComicsTest are NOT “out of scope”. I am not sure why this works yet when i do arrayOfComics they are out of scope. arrayOfComics is a class variable NSMutableArray * arrayOfComics in the .h. It is not used anywhere until this point.

NSMutableArray * arrayOfComicsTest = [NSMutableArray arrayWithArray:ComicArray];

Answer 1

At the time I was having a bunch of problems because I did not fully understand the difference between mutable and non mutable arrays, as well as the various return values from array operations.

I eventually fixed this by making a bunch of changes.

Thanks to everyone that provided help.