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Swipe to delete a cell in a table using NSFetchedResultsController

I previously had a working implementation in which I had one TableViewController, I press the ADD button, it calls another view controller that allows the user to add text to the fields - this, in turn, adds this information to entities and attributes and I could display this in a table view. By implementing the following methods, I could successfully delete the line:

- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
    return YES;
}

- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{

    if (editingStyle == UITableViewCellEditingStyleDelete)
    {
        [self.managedObjectContext deleteObject:[self.transactions objectAtIndex:indexPath.row]];
        [self.transactions removeObjectAtIndex:indexPath.row];
        [self.tableView reloadData];

        NSError *error = nil;
        if (![self.managedObjectContext save:&error])
        {
            NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
            abort();
            [self.tableView reloadData];
        }
    }

}

Now I was able to successfully implement the NSFetchedResultsController to provide the same functionality with adding and retrieving information, but just more secure. Now I can’t understand how to actually implement the same swipe to remove functionality.

I added:

- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
    return YES;
}

, "" .

NSFetchedReusltsController :

- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type newIndexPath:(NSIndexPath *)newIndexPath {

    UITableView *tableView = self.tableView;

    switch(type) {

        case NSFetchedResultsChangeInsert:
            [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;

        case NSFetchedResultsChangeDelete:
            [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;

        case NSFetchedResultsChangeUpdate:
            [self configureCell:[tableView cellForRowAtIndexPath:indexPath] atIndexPath:indexPath];
            break;

        case NSFetchedResultsChangeMove:
            [tableView deleteRowsAtIndexPaths:[NSArray
                                               arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
            [tableView insertRowsAtIndexPaths:[NSArray
                                               arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;
    }
}

, .

.

+4
1

, Core Data:

if (editingStyle == UITableViewCellEditingStyleDelete)
{
    [self.managedObjectContext deleteObject:[self.fetchedResultsController objectAtIndexPath:indexPath]];

    NSError *error = nil;
    if (![self.managedObjectContext save:&error]) {
        // handle error
    }
}

, , reloadData. , .

, self.transactions. , . .

+11

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