Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid update: invalid number of rows in section 0

Question

Thanks in advance. Please help me to find out error.

In my application, I have expandable tableview. Application get crashed when I try to show all rows in section.

for (int i=0; i<rows; i++)
                {
                    NSIndexPath *tmpIndexPath = [NSIndexPath indexPathForRow:i
                                                                   inSection:section];
                    [tmpArray addObject:tmpIndexPath];
                }

but work fine if loop is like in tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath

for (int i=1; i<rows; i++)
                {
                    NSIndexPath *tmpIndexPath = [NSIndexPath indexPathForRow:i
                                                                   inSection:section];
                    [tmpArray addObject:tmpIndexPath];
                }

Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid update: invalid number of rows in section 0. The number of rows contained in an existing section after the update (6) must be equal to the number of rows contained in that section before the update (1), plus or minus the number of rows inserted or deleted from that section (6 inserted, 0 deleted) and plus or minus the number of rows moved into or out of that section (0 moved in, 0 moved out).'

*** First throw call stack:
(
    0   CoreFoundation                      0x02d9c5e4 __exceptionPreprocess + 180
    1   libobjc.A.dylib                     0x02b1f8b6 objc_exception_throw + 44
    2   CoreFoundation                      0x02d9c448 +[NSException raise:format:arguments:] + 136
    3   Foundation                          0x0270023e -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 116
    4   UIKit                               0x0196320d -[UITableView _endCellAnimationsWithContext:] + 13402
    5   UIKit                               0x01972c60 -[UITableView _updateRowsAtIndexPaths:updateAction:withRowAnimation:] + 337
    6   UIKit                               0x01972c9f -[UITableView insertRowsAtIndexPaths:withRowAnimation:] + 55
    7   UIKit                               0x0dceada5 -[UITableViewAccessibility(Accessibility) insertRowsAtIndexPaths:withRowAnimation:] + 65
    8   BPSSalesDocs                        0x00222d10 -[MiddlePageViewController_iPhone tableView:didSelectRowAtIndexPath:] + 1152
    9   UIKit                               0x01973ec1 -[UITableView _selectRowAtIndexPath:animated:scrollPosition:notifyDelegate:] + 1513
    10  UIKit                               0x01974034 -[UITableView _userSelectRowAtPendingSelectionIndexPath:] + 279
    11  UIKit                               0x01978018 __38-[UITableView touchesEnded:withEvent:]_block_invoke + 43
    12  UIKit                               0x018aed33 ___afterCACommitHandler_block_invoke + 15
    13  UIKit                               0x018aecde _applyBlockToCFArrayCopiedToStack + 403
    14  UIKit                               0x018aeb0a _afterCACommitHandler + 532
    15  CoreFoundation                      0x02d6453e __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 30
    16  CoreFoundation                      0x02d6448f __CFRunLoopDoObservers + 399
    17  CoreFoundation                      0x02d423b4 __CFRunLoopRun + 1076
    18  CoreFoundation                      0x02d41b33 CFRunLoopRunSpecific + 467
    19  CoreFoundation                      0x02d4194b CFRunLoopRunInMode + 123
    20  GraphicsServices                    0x04b449d7 GSEventRunModal + 192
    21  GraphicsServices                    0x04b447fe GSEventRun + 104
    22  UIKit                               0x0189294b UIApplicationMain + 1225
    23  BPSSalesDocs                        0x001c8a3d main + 141
    24  libdyld.dylib                       0x03822725 start + 0
)
libc++abi.dylib: terminating with uncaught exception of type NSException

Below is the code for UITable View didSelectRowAtIndexPath

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    _ParentCollection = [[Content alloc] initWithDictionary:[_collections objectAtIndex:indexPath.section]];
    [self performSelectorOnMainThread:@selector(loadChildCollection:) withObject:[_ParentCollection collectionId] waitUntilDone:YES];
    if ([_childCollections count] > 0) {
        if ([self tableView:tableView canCollapseSection:indexPath.section]) {
            if (!indexPath.row) {
                [tableView deselectRowAtIndexPath:indexPath animated:YES];

                NSInteger section = indexPath.section;
                BOOL currentlyExpanded = [_expandedSections containsIndex:section];
                NSInteger rows;

                NSMutableArray *tmpArray = [NSMutableArray array];

                if (currentlyExpanded)
                {
                    rows = [self tableView:tableView numberOfRowsInSection:section];
                    [_expandedSections removeIndex:section];
                }
                else
                {
                    [_expandedSections addIndex:section];
                    rows = [self tableView:tableView numberOfRowsInSection:section];
                }

                for (int i=0; i<rows; i++)
                {
                    NSIndexPath *tmpIndexPath = [NSIndexPath indexPathForRow:i
                                                                   inSection:section];
                    [tmpArray addObject:tmpIndexPath];
                }

                if (currentlyExpanded)
                {
                    [tableView deleteRowsAtIndexPaths:tmpArray
                                     withRowAnimation:UITableViewRowAnimationTop];
                }
                else
                {
                    [tableView insertRowsAtIndexPaths:tmpArray
                                     withRowAnimation:UITableViewRowAnimationTop];
                }
            }
            else {
                self.childCollectionContent = [[Content alloc] initWithDictionary:[self.childCollections objectAtIndex:indexPath.row]];

                UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:[DeviceHelper getStoryboardName] bundle:nil];

                ContentViewController *contentViewController = (ContentViewController*)[mainStoryboard instantiateViewControllerWithIdentifier: @"ContentViewController"];
                [contentViewController setNavigationalContents:_childCollections];
                [contentViewController setCollectionId:[NSString stringWithFormat:@"%@", [self.childCollectionContent collectionId]]];
                [contentViewController setContentId:[self.childCollectionContent contentId]];
                [contentViewController setTitle:[self.childCollectionContent title]];
                [contentViewController setContentType:[self.childCollectionContent type]];


                //        [contentViewController setContentUpdateDelegate:_contentUpdateDelegate];
                //        [contentViewController setContentNavigationDelegate:_contentNavigationDelegate];

                if ([[[AppService sharedService] mainViewController] isKindOfClass:[UINavigationController class]]) {
                    UINavigationController* navigationController = (UINavigationController*)[[AppService sharedService] mainViewController];
                    navigationController.navigationBarHidden  = NO;
                    [navigationController pushViewController:contentViewController animated:YES];
                    NSDictionary *attributes = @{NSForegroundColorAttributeName: [UIColor whiteColor]};
                    [[navigationController navigationBar] setTitleTextAttributes:attributes];

                } else {
                    [[[AppService sharedService] mainViewController] presentViewController:contentViewController animated:YES completion:nil];
                }

                AnalyticsClicked* analyticsClicked = [[AnalyticsClicked alloc] init];
                analyticsClicked.collectionId = [self.childCollectionContent collectionId];
                analyticsClicked.contentId = [self.childCollectionContent contentId];
                analyticsClicked.contentNumber = [self.childCollectionContent contentNumber];

                [[[AppService sharedService] analytics] platformAnalyticsContentClickPush:analyticsClicked];
            }
        }
    }
}

and numberOfRowsInSections code

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
//    return [_collections count];
    if ([self tableView:tableView canCollapseSection:section]) {
        if ([_expandedSections containsIndex:section]) {
            return [_childCollections count];
        }
    }
    return 1;
}

Answer 1

I finally able to overcomer that error. In my didSelectRowAtIndexPath i changed below code

if (currentlyExpanded)
                {
                    [tableView deleteRowsAtIndexPaths:tmpArray
                                     withRowAnimation:UITableViewRowAnimationTop];
                }
                else
                {
                    [tableView insertRowsAtIndexPaths:tmpArray
                                     withRowAnimation:UITableViewRowAnimationTop];
                }

with

if (currentlyExpanded)
                {
                    [tableView beginUpdates];
                    [tableView reloadSections:[NSIndexSet indexSetWithIndex:indexPath.section] withRowAnimation:UITableViewRowAnimationTop];
                    [tableView deleteRowsAtIndexPaths:tmpArray
                                     withRowAnimation:UITableViewRowAnimationTop];
                    [tableView endUpdates];
                }
                else
                {
                    [tableView beginUpdates];
                    [tableView reloadSections:[NSIndexSet indexSetWithIndex:indexPath.section] withRowAnimation:UITableViewRowAnimationTop];
                    [tableView insertRowsAtIndexPaths:tmpArray
                                     withRowAnimation:UITableViewRowAnimationTop];
                    [tableView endUpdates];
                }

I think problem was due to mismatch of number of rows before update and after update which get resolved just by calling

[tableView reloadSections:[NSIndexSet indexSetWithIndex:indexPath.section]

which reset the rows count. Please correct me if any one want to improve or correct this.