Core Data Serious Application Error at controllerDidChangeContent

问题

Hello I am stacked now with the error below.

CoreData: error: Serious application error.
An exception was caught from the delegate of NSFetchedResultsController during a call to -controllerDidChangeContent:.
Invalid update: invalid number of sections.
The number of sections contained in the table view after the update (7) must be equal to the number of sections contained in the table view before the update (6), plus or minus the number of sections inserted or deleted (0 inserted, 0 deleted). with userInfo (null)

My application has multiple sections tableView. And error only occurs when I try to insert new section record. If the section already exists, error not occurred.

The related code is following.

- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller
{
    [self.tableView beginUpdates];
}

- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject
       atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type
       newIndexPath:(NSIndexPath *)newIndexPath
{
     UITableView *tableView = self.tableView;
     DLog(@"newIndexPath %@",newIndexPath);
    switch(type) {
        case NSFetchedResultsChangeInsert:
            [tableView insertRowsAtIndexPaths:@[newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;

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

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

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

- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller
{
    /*NSError *error = nil;
    if (![[self fetchedResultsController] performFetch:&error]) {
        DLog(@"Unresolved error %@, %@", error, [error userInfo]);
        abort();
    }
    [self.tableView reloadData];*/
    [self.tableView endUpdates];
}

Also I put sectionNameKeyPath at fetchResultsController. year column does not exist in real core data, it is extension column.

    NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:self.managedObjectContext sectionNameKeyPath:@"year" cacheName:@"Master"];

回答1:

I could resolve the error by the following changes. Just for someone in the same situation.

I commented out the following line.

- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller
{
    [self.tableView beginUpdates];
}

- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject
       atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type
      newIndexPath:(NSIndexPath *)newIndexPath
{
    UITableView *tableView = self.tableView;
    DLog(@"newIndexPath %@",newIndexPath);
    switch(type) {
        case NSFetchedResultsChangeInsert:
            [tableView insertRowsAtIndexPaths:@[newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;

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

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

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

- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller
{
    [self.tableView endUpdates];
}

And I added the following line.

 - (void)controllerDidChangeContent:(NSFetchedResultsController *)controller
 {
 // In the simplest, most efficient, case, reload the table view.
     NSError *error = nil;
     if (![[self fetchedResultsController] performFetch:&error]) {
         DLog(@"Unresolved error %@, %@", error, [error userInfo]);
         abort();
     }
     [self.tableView reloadData];
 }

来源：https://stackoverflow.com/questions/24601064/core-data-serious-application-error-at-controllerdidchangecontent

标签

ios

objective-c

uitableview

core-data

nsfetchedresultscontroller