App crashes on call to 'tableView endUpdates' - ios

Question

I'm currently working on an implementation of an inline UIDate picker inside of a UITableViewCell.
I'm able to show and hide this picker cell when I select the cell directly above where that cell should be inserted, which is the behavior that I expect. However, the app crashes if I select any other cells in the table view:
*** Assertion failure in -[UITableView _endCellAnimationsWithContext:], /SourceCache/UIKit_Sim/UIKit-3318.16.14/UITableView.m:1582
After looking at the accepted answer to this SO question, I added an exception breakpoint, and I've found out that the app is crashing at the call to [tableView endUpdates]; in didSelectRowAtIndexPath:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
[self.tableView deselectRowAtIndexPath:indexPath animated:YES];
// Check to see if the "Only Alert From" row was selected. The cell with the picker should be below this one.
if (indexPath.section == TimeOfDaySection && indexPath.row == HourTimeZoneRow && self.timePickerIsShowing == NO){
[tableView beginUpdates];
[self showTimePicker];
[tableView endUpdates];
} else{
[tableView beginUpdates];
[self hideTimePicker];
[tableView endUpdates];
[self.tableView deselectRowAtIndexPath:indexPath animated:YES];
}
[self.tableView deselectRowAtIndexPath:indexPath animated:YES];
}
That said, I'm not sure how to proceed. If I comment out the call to [tableView endUpdates];, the app won't crash when other cells are selected, BUT the cell with the picker view won't hide. Does anyone have any suggestions? Thank you!
EDIT: Below is my code for showTimePicker and hideTimePicker:
- (void)showTimePicker
{
self.timePickerIsShowing = YES;
self.timePicker.hidden = NO;
//Create the index path where we insert the cell with the picker
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:HourTimeZoneRow + 1 inSection:TimeOfDaySection];
[self.tableView beginUpdates];
[self.tableView insertRowsAtIndexPaths:#[indexPath] withRowAnimation:UITableViewRowAnimationFade];
[self.tableView endUpdates];
self.timePicker.alpha = 0.0f;
[UIView animateWithDuration:0.25 animations:^{
self.timePicker.alpha = 1.0f;
//This is the row where the picker cell should be inserted
[self.tableView reloadRowsAtIndexPaths:#[[NSIndexPath indexPathForRow:HourTimeZoneRow + 1 inSection:TimeOfDaySection]] withRowAnimation:UITableViewRowAnimationFade];
[self.tableView reloadData];
}];
}
- (void)hideTimePicker {
self.timePickerIsShowing = NO;
self.timePicker.hidden = YES;
//Create the index path where we delete the cell with the picker
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:HourTimeZoneRow + 1 inSection:TimeOfDaySection];
[self.tableView beginUpdates];
//Delete the picker row
[self.tableView deleteRowsAtIndexPaths:#[indexPath] withRowAnimation:UITableViewRowAnimationFade];
[self.tableView endUpdates];
[UIView animateWithDuration:0.25
animations:^{
self.timePicker.alpha = 0.0f;
}
completion:^(BOOL finished){
self.timePicker.hidden = YES;
}];
}
EDIT 2: After reading this SO thread, I believe the problem may be with my numberOfRowsInSection method:
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
switch (section) {
case NotificationsSection:
return TotalPreferencesRows;
break;
case RedZoneSection:
return TotalRedZoneRows;
break;
case TimeOfDaySection:
if (self.timePickerIsShowing) {
return TotalTimeOfDayRows + 1;
}
// else if (self.timePickerIsShowing == NO){
// return TotalTimeOfDayRows;
// }
else{
return TotalTimeOfDayRows;
}
return TotalTimeOfDayRows;
break;
default:
return 0;
break;
}
}

Answer 1

Not sure if this is the source of the crash, but it's not recommended to call beginUpdates multiple times which you're doing in
[tableView beginUpdates];
[self showTimePicker];
[tableView endUpdates];
because showTimePicker calls [self.tableView beginUpdates];

Answer 2

The problem is in your didSelectRowAtIndexPath, you call the hide method even though it might not be showing. Make the else clause into an else if, like this:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
[self.tableView deselectRowAtIndexPath:indexPath animated:YES];
// Check to see if the "Only Alert From" row was selected. The cell with the picker should be below this one.
if (indexPath.section == TimeOfDaySection && indexPath.row == HourTimeZoneRow && self.timePickerIsShowing == NO){
[tableView beginUpdates];
[self showTimePicker];
[tableView endUpdates];
} else if (indexPath.section == TimeOfDaySection && indexPath.row == HourTimeZoneRow && self.timePickerIsShowing == YES){
[tableView beginUpdates];
[self hideTimePicker];
[tableView endUpdates];
[self.tableView deselectRowAtIndexPath:indexPath animated:YES];
}
[self.tableView deselectRowAtIndexPath:indexPath animated:YES];
}