Question

I am a new in objective-c, I want to know when I return an object like the code below, whether I should autorelease it like this:

- (NSArray *)loadCategory
{
    NSArray *temp = [[[NSArray alloc] initWithObjects:c1, c2, nil] autorelease];

    return temp;
}

More, When I use call function to get the return value, whether I should retain the objective?

- (void)viewDidLoad
{
     category = [self loadCategory];

     [category retain];

   [super viewDidLoad];
}

Finally, can I replace with:

- (void)viewDidLoad
    {
        self.category = [self loadCategory];
       [super viewDidLoad];
    } 

Answer 1

Your code is fine.
You could alternatively use…

[NSArray arrayWithObjects: …, nil];

This will return an auto-release instance for you.

Also don’t forget to call release on this array if you retain it after you no longer need it.