Question

[EDIT] I am changing this to more concisely explain what my problem was, after having more precisely pinpointed the issue.

I am working on core data for my app, but am stumped. It hangs in this method every time. No crashes, no logs, no nothing. It just hangs.

- (void)insertNewObject:(id)sender
{
    NSManagedObjectContext *context = [self.fetchedResultsController managedObjectContext];
    NSEntityDescription *entity = [[self.fetchedResultsController fetchRequest] entity];
    NSManagedObject *newObject = [NSEntityDescription insertNewObjectForEntityForName:[entity name] inManagedObjectContext:context];

    Section *newSection = (Section *)newObject;
    newSection.title = @"inserted";


    NSError *error = nil;

    if (![context save:&error]) {

        NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
        abort();
    }
}

NSManagedObject *newObject = [NSEntityDescription insertNewObjectForEntityForName:[entity name] inManagedObjectContext:context];

I discovered that if I put NSLogs in these two delegate methods:

- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller
- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller

they just keep getting called infinite number of times.

Answer 1

Ok, I figured it out. I was creating an infinite loop.

This delegate method gets called:

- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller

Then this eventually gets called because I called [self.tableView beginUpdates]; in the delegate method.

- (void)configureCell:(UITableViewCell *)cell atIndexPath:(NSIndexPath *)indexPath

    {
        Section *object = [self.fetchedResultsController objectAtIndexPath:indexPath];
        object.title = [NSString stringWithFormat:@"Chapter %i", indexPath.row];
        cell.textLabel.text = object.title;

    }

Then this delegate method:

- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller

The the problem is that I was actually changing the NSManagedObject’s attributes while it was updating the content

object.title = [NSString stringWithFormat:@"Chapter %i", indexPath.row];

this caused controllerWillChangeContent: to be called once again creating a loop that just goes round and round.