Assertion Failure when updating uitableview - ios

Question

I get this assertion when trying to update my tableview when clicking on a section header.
* Assertion failure in -[UITableView _endCellAnimationsWithContext:], /SourceCache/UIKit_Sim/UIKit-2839.5/UITableView.m:1264
I am just trying to hide and show custom cells whenever I click on a section header view.
code works fine if I replace the update code with reload data. but that's not smooth :(
- (void)noteSectionHeader:(UTNoteSectionHeader *)noteSectionHeader sectionTapped:(NSInteger)section
{
UTNoteItem* noteItem = self.notes[section];
BOOL alreadySelected = noteItem.selected;
if (alreadySelected) {
self.selectedSection = NSNotFound;
[self setSelected:NO forSection:section];
}
else {
self.selectedSection = section;
[self setSelected:YES forSection:section];
}
[self updateSections];
}
- (void)setSelected:(BOOL)selected forSection:(NSInteger)section
{
UTNoteItem* noteItem = self.notes[section];
noteItem.selected = selected;
for (UTNoteItem* tmpItem in self.notes) {
if (tmpItem != noteItem) {
tmpItem.selected = NO;
}
}
}
- (void)updateSections
{
NSMutableArray* deletePaths = [[NSMutableArray alloc] init];
NSMutableArray* addPaths = [[NSMutableArray alloc] init];
for (UTNoteItem* item in self.notes) {
if (item.selected) {
[addPaths addObject:[NSIndexPath indexPathForRow:0 inSection:[self.notes indexOfObject:item]]];
}
else {
[deletePaths addObject:[NSIndexPath indexPathForRow:0 inSection:[self.notes indexOfObject:item]]];
}
}
[self.tableView beginUpdates];
[self.tableView deleteRowsAtIndexPaths:deletePaths withRowAnimation:YES];
[self.tableView insertRowsAtIndexPaths:addPaths withRowAnimation:YES];
[self.tableView endUpdates];
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return self.notes.count;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
UTNoteItem* itemNote = self.notes[section];
if (itemNote.selected) return 1;
return 0;
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return 40;
}
EDIT:
Here is my new implementation:
-
(void)noteSectionHeader:(UTNoteSectionHeader *)noteSectionHeader sectionTapped:(NSInteger)section
{
/* Check if a section is opened */
if (self.selectedSection != NSNotFound) {
/* A section is open, get the item */
UTNoteItem* theItem = self.notes[self.selectedSection];
/* if the item is the section opened, close it */
if (self.selectedSection == section) {
theItem.selected = NO;
self.selectedSection = NSNotFound;
}
/* The item is not the section, so open it, and close the previous item */
else {
theItem.selected = YES;
UTNoteItem* prevItem = self.notes[self.selectedSection];
prevItem.selected = NO;
self.selectedSection = section;
}
}
/* Nothin is open, just open the section */
else {
self.selectedSection = section;
UTNoteItem* openItem = self.notes[self.selectedSection];
openItem.selected = YES;
}
/* Reload the selected section.. this will not reload the other sections? */
[self.tableView reloadSections:[NSIndexSet indexSetWithIndex:section] withRowAnimation:UITableViewRowAnimationAutomatic];
}

Answer 1

I have had a similar problem, however I perform a reload like so:
- (void)noteSectionHeader:(UTNoteSectionHeader *)noteSectionHeader sectionTapped:(NSInteger)section
{
//check our action
if(<will hide section>) {
//hide section
<some action>
} else {
//show section
<some action>
}
[self.tableView reloadSections:[NSIndexSet indexSetWithIndex:indexPath.section] withRowAnimation:UITableViewRowAnimationAutomatic];
}
and it reloads again differently with a forced update:
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
NSInteger nRows = 0; //no rows when closed
if(<check section is open>) {
nRows +=<number of data items shown>;
}
return nRows;
}
Where the indexpath.section is the section I wish to hide or show. it is smooth and stable.
Deleting and adding rows is a little dangerous in my opinion, tableviews are very good at doing animated reloads on individual sections or cells.