Terminating app due to uncaught exception 'NSInternalInconsistencyException'

Question

If user touch the UITableView and just Update the TableView for following code

[self.myTableView beginUpdates];
[myTableView endUpdates];

then it produce the following crash report.

2013-12-17 17:27:33.446 planobot[12300:a0b] *** Assertion failure in -[UITableView _endCellAnimationsWithContext:], /SourceCache/UIKit_Sim/UIKit-2903.23/UITableView.m:1330
2013-12-17 17:27:33.469 planobot[12300:a0b] *** 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 (1) must be equal to the number of rows contained in that section before the update (7), plus or minus the number of rows inserted or deleted from that section (0 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                      0x0210e5e4 __exceptionPreprocess + 180
    1   libobjc.A.dylib                     0x01e918b6 objc_exception_throw + 44
    2   CoreFoundation                      0x0210e448 +[NSException raise:format:arguments:] + 136
    3   Foundation                          0x00fe5fee -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 116
    4   UIKit                               0x0024485d -[UITableView _endCellAnimationsWithContext:] + 13402
    5   UIKit                               0x00253caa -[UITableView endUpdatesWithContext:] + 51
    6   UIKit                               0x00253cd8 -[UITableView endUpdates] + 41
    7   planobot                            0x0004f34a -[DailyReportViewController tableView:didSelectRowAtIndexPath:] + 1658
    8   UIKit                               0x002557b1 -[UITableView _selectRowAtIndexPath:animated:scrollPosition:notifyDelegate:] + 1513
    9   UIKit                               0x00255924 -[UITableView _userSelectRowAtPendingSelectionIndexPath:] + 279
    10  UIKit                               0x00259908 __38-[UITableView touchesEnded:withEvent:]_block_invoke + 43
    11  UIKit                               0x00190183 ___afterCACommitHandler_block_invoke + 15
    12  UIKit                               0x0019012e _applyBlockToCFArrayCopiedToStack + 403
    13  UIKit                               0x0018ff5a _afterCACommitHandler + 532
    14  CoreFoundation                      0x020d64ce __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 30
    15  CoreFoundation                      0x020d641f __CFRunLoopDoObservers + 399
    16  CoreFoundation                      0x020b4344 __CFRunLoopRun + 1076
    17  CoreFoundation                      0x020b3ac3 CFRunLoopRunSpecific + 467
    18  CoreFoundation                      0x020b38db CFRunLoopRunInMode + 123
    19  GraphicsServices                    0x02fec9e2 GSEventRunModal + 192
    20  GraphicsServices                    0x02fec809 GSEventRun + 104
    21  UIKit                               0x00173d3b UIApplicationMain + 1225
    22  planobot                            0x000a6a4d main + 141
    23  planobot                            0x000022b5 start + 53
)
libc++abi.dylib: terminating with uncaught exception of type NSException

Why is the application throwing a NSInternalInconsistencyException?

Answer 1

I often see this when my count is not correct. Based on this:

reason: 'Invalid update: invalid number of rows in section 0.  The number of rows contained in an existing section after the update (1) must be equal to the number of rows contained in that section before the update (7), plus or minus the number of rows inserted or deleted from that section (0 inserted, 0 deleted) and plus or minus the number of rows moved into or out of that section (0 moved in, 0 moved out).'

I'm guessing that your table had 7 elements in it (as reported by tableView:numberOfRowsInSection:) was returning 7 and now is returning 1. Which leads me to belive you think calling

 [self.myTableView beginUpdates];
 [myTableView endUpdates];

Is sufficient when you are removing rows.

But you need to tell you UITableView what rows are being removed (or added) first. This will depend on your exact situation, but if you wanted to remove the first seven rows of section zero it would look like this.

NSMutableArray *indexes = [[NSMutableArray alloc] init];
for (int i = 0; i <= 6; i++)
{
    [indexes addObject:[NSIndexPath indexPathForItem:i inSection:0]];
}
[myTable beginUpdates];
[myTable deleteRowsAtIndexPaths:indexes withRowAnimation:NO];
[myTable endUpdates];

Also as @Marco said, just use the same pointer to your table otherwise it's a bit confusing, which I did in my example.

Or if you just wanted to tell you table to completly reload you can just call reloadData instaed.

[myTable reloadData];

I think this would be less efficient then the other way of manually specify which rows are being added or removed, but in a table of 7 I think it would be fine.

Answer 2

Instead of this:

[self.myTableView beginUpdates];
[myTableView endUpdates];

try this:

[self.myTableView beginUpdates];
[self.myTableView endUpdates];

I suspect endUpdates is not getting called on your myTableView property. beginUpdates is, however, which leads to:

1. Unbalanced beginUpdates / endUpdates calls and
2. NSInternalInconsistencyException