iPhone: Core Data saving error

Question

I am getting the following error when trying to save an object into my core data model:

2010-09-01 22:07:50.569 Score Card[26566:207] *** Assertion failure in -[UITableView _endCellAnimationsWithContext:], /SourceCache/UIKit_Sim/UIKit-1262.60.3/UITableView.m:904
2010-09-01 22:07:50.570 Score Card[26566:207] Serious application error.  Exception was caught during Core Data change processing.  This is usually a bug within an observer of NSManagedObjectContextObjectsDidChangeNotification.  Invalid update: invalid number of sections.  The number of sections contained in the table view after the update (1) must be equal to the number of sections contained in the table view before the update (1), plus or minus the number of sections inserted or deleted (1 inserted, 0 deleted). with userInfo (null)
Detected an attempt to call a symbol in system libraries that is not present on the iPhone:
_Unwind_Resume called from function -[NSManagedObjectContext(_NSInternalChangeProcessing) _processRecentChanges:] in image CoreData.
2010-09-01 22:07:50.572 Score Card[26566:207] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid update: invalid number of sections.  The number of sections contained in the table view after the update (1) must be equal to the number of sections contained in the table view before the update (1), plus or minus the number of sections inserted or deleted (1 inserted, 0 deleted).'
*** Call stack at first throw:
(
 0   CoreFoundation                      0x02661b99 __exceptionPreprocess + 185
 1   libobjc.A.dylib                     0x027b140e objc_exception_throw + 47
 2   CoreFoundation                      0x0261a238 +[NSException raise:format:arguments:] + 136
 3   Foundation                          0x000bae37 -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 116
 4   UIKit                               0x0033a9a6 -[UITableView(_UITableViewPrivate) _endCellAnimationsWithContext:] + 7806
 5   UIKit                               0x0032a75b -[UITableView insertSections:withRowAnimation:] + 56
 6   Score Card                          0x00003918 -[History controller:didChangeSection:atIndex:forChangeType:] + 133
 7   CoreData                            0x0246db81 -[NSFetchedResultsController(PrivateMethods) _managedObjectContextDidChange:] + 2177
 8   Foundation                          0x0002a0e1 _nsnote_callback + 145
 9   CoreFoundation                      0x02639f29 __CFXNotificationPost_old + 745
 10  CoreFoundation                      0x025b926a _CFXNotificationPostNotification + 186
 11  Foundation                          0x0001fc8a -[NSNotificationCenter postNotificationName:object:userInfo:] + 134
 12  CoreData                            0x023a8879 -[NSManagedObjectContext(_NSInternalNotificationHandling) _postObjectsDidChangeNotificationWithUserInfo:] + 89
 13  CoreData                            0x02418193 -[NSManagedObjectContext(_NSInternalChangeProcessing) _createAndPostChangeNotification:withDeletions:withUpdates:withRefreshes:] + 259
 14  CoreData                            0x0238b208 -[NSManagedObjectContext(_NSInternalChangeProcessing) _processRecentChanges:] + 1352
 15  CoreData                            0x023c4e55 -[NSManagedObjectContext save:] + 149
 16  Score Card                          0x000053ad -[TimeRun saveAction] + 65
 17  Score Card                          0x00004116 -[TimeRun countDown] + 326
 18  Foundation                          0x000561c9 __NSFireTimer + 125
 19  CoreFoundation                      0x02642f73 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 19
 20  CoreFoundation                      0x026445b4 __CFRunLoopDoTimer + 1364
 21  CoreFoundation                      0x025a0dd9 __CFRunLoopRun + 1817
 22  CoreFoundation                      0x025a0350 CFRunLoopRunSpecific + 208
 23  CoreFoundation                      0x025a0271 CFRunLoopRunInMode + 97
 24  GraphicsServices                    0x02f4000c GSEventRunModal + 217
 25  GraphicsServices                    0x02f400d1 GSEventRun + 115
 26  UIKit                               0x002ceaf2 UIApplicationMain + 1160
 27  Score Card                          0x00002998 main + 102
 28  Score Card                          0x00002929 start + 53
)
terminate called after throwing an instance of 'NSException

I am just not sure how to fix the issue. I am not inserting any sections, so I am at a loss here. Ideas?

EDIT:

Does it have to do with how I am fetching my results? It seems I am using a key for section name, but I don't want sections:

- (NSFetchedResultsController *)fetchedResultsController {

    if (fetchedResultsController != nil) {
        return fetchedResultsController;
    }

    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Mission" inManagedObjectContext:managedObjectContext];
    [fetchRequest setEntity:entity];

    // Create the sort descriptors array.
    NSSortDescriptor *startDescriptor = [[NSSortDescriptor alloc] initWithKey:@"title" ascending:YES];
    NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:startDescriptor, nil];
    [fetchRequest setSortDescriptors:sortDescriptors];

    // Create and initialize the fetch results controller.
    NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:managedObjectContext sectionNameKeyPath:@"title" cacheName:@"Root"];
    self.fetchedResultsController = aFetchedResultsController;
    self.fetchedResultsController.delegate = self;

    // Memory management.
    [aFetchedResultsController release];
    [fetchRequest release];
    [startDescriptor release];
    [sortDescriptors release];

    return fetchedResultsController;

}//end

Answer 1

they say you delete the app in your simulator then "Clean all build targets" then rebuild and run again. Hope this helps

I based my answer on: 'NSInternalInconsistencyException'

Answer 2

This tells you your problem:

Invalid update: invalid number of sections. The number of sections contained in the table view after the update (1) must be equal to the number of sections contained in the table view before the update (1), plus or minus the number of sections inserted or deleted (1 inserted, 0 deleted).

After the update, you are returning the incorrect number of sections from 'numberOfSectionsInTableView:`. Most likely, something in update changes the sections but you keep returning the old section number count.

Answer 3

Setting sectionNameKeyPath: to nil has fixed my issue.