Help with NSFetchedResultsController - objective-c

Question

Please help with this issue of using NSFetchedResultsController.
I created an object of NSFetchedResultsController and I use it once in the method: tableView:cellForRowAtIndexPath: and when I try to execute the same code in the method tableView:didSelectRowAtIndexPath: I get EXC_BAD_ACCESS.
Here is the code of the 2 methods
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
}
Person *person = [fetchedResultsController objectAtIndexPath:indexPath];
cell.textLabel.text = person.name; //This works fine
[person release];
return cell;
}
and here is the problematic snippet:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
PhotoListViewController *photoListViewController = [[PhotoListViewController alloc] initWithNibName:#"PhotoListViewController" bundle:nil];
//The next line returns a bad object or undefined memory
Person *person = [fetchedResultsController objectAtIndexPath:indexPath];
//causing the call of [person name] to return EXC_BAD_ACCESS
photoListViewController.person = [person name];
[self.navigationController pushViewController:photoListViewController animated:YES];
[photoListViewController release];
[person release];
}
Please help me understand why the code is breaking there.
Appreciate any suggestions.

Answer 1

Person *person = [fetchedResultsController objectAtIndexPath:indexPath];
cell.textLabel.text = person.name; //This works fine
[person release];
[person release] is the problem - no need to release person if it's not alloc'd there. That causes person to be over-released, leading to the crash when something else tries to access it.

Answer 2

Even though, in this example, it's ok to manipulate an autoreleased object (due to simplicity of the manipulations, i.e. you are just grabbing one property of *person), the proper way would be to retain your Person object and release it at the end:
Person *person = [[fetchedResultsController objectAtIndexPath:indexPath] retain];
// bla bla
[person release];