uitableview crashed when scrolling - ios

Question

i am developing an app with the help of this example in my app and everything is working as required but when i expand the expended cell and scroll down app crashes when table reaches at the end. let me post all my code here.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
FSParallaxTableViewCell *cell = nil;
static NSString *cellIdentifier = nil;
// init expanded cell
if ([indexPath isEqual:self.expandedIndexPath]) {
cellIdentifier = #"ExpandedCellIdentifier";
}
// init expanding cell
else {
cellIdentifier = #"Cell";
}
cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier forIndexPath:indexPath];
if (cell == nil) {
cell = [[FSParallaxTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
cell.cellImageView.image = [UIImage imageNamed:#"placeholder.png"];
}
if ([[cell reuseIdentifier] isEqualToString:#"ExpandedCellIdentifier"]) {
cell.playIconBig = [UIButton buttonWithType:UIButtonTypeRoundedRect];
cell.playIconBig.tag= indexPath.row-1;
[cell.playIconBig addTarget:self action:#selector(play:) forControlEvents:UIControlEventTouchDown];
cell.playIconBig.frame = CGRectMake(25, 5, 25, 25);
[cell.playIconBig setBackgroundImage:[UIImage imageNamed:#"play_expand.png"] forState:UIControlStateNormal];
[cell.contentView addSubview:cell.playIconBig];
}
// set text in expanding cell
if ([[cell reuseIdentifier] isEqualToString:#"Cell"]) {
[cell.cellImageView sd_setImageWithURL:[NSURL URLWithString:[[rssOutputData objectAtIndex:indexPath.row]xmllink]] placeholderImage:[UIImage imageNamed:#"placeholder"] options:indexPath.row == 0 ? SDWebImageRefreshCached : 0];
cell.clipsToBounds = YES;
//[cell.contentView addSubview:arrowImg];
cell.song.text = [[rssOutputData objectAtIndex:indexPath.row]xmltitle];
cell.artist.text = [NSString stringWithFormat:#"By %#",[[rssOutputData objectAtIndex:indexPath.row]xmlsinger]];
cell.share.text = [[rssOutputData objectAtIndex:indexPath.row]xmllikes];
cell.download.text = [[rssOutputData objectAtIndex:indexPath.row]xmldownloads];
}
// set text in expanding cell
if ([[cell reuseIdentifier] isEqualToString:#"Cell"]) {
[cell.cellImageView sd_setImageWithURL:[NSURL URLWithString:[[rssOutputData objectAtIndex:indexPath.row]xmllink]] placeholderImage:[UIImage imageNamed:#"placeholder"] options:indexPath.row == 0 ? SDWebImageRefreshCached : 0];
cell.clipsToBounds = YES;
//[cell.contentView addSubview:arrowImg];
cell.song.text = [[rssOutputData objectAtIndex:indexPath.row]xmltitle];
cell.artist.text = [NSString stringWithFormat:#"By %#",[[rssOutputData objectAtIndex:indexPath.row]xmlsinger]];
}
return cell;
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
// take expanded cell into account when returning number of rows
if (self.expandedIndexPath) {
return [rssOutputData count] + 1;
}
return [rssOutputData count];
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
if ([indexPath isEqual:self.expandedIndexPath])
{
return 40;//height for expanded
} else {
return 140;//height for normal
}
}
and here didselectrowatindexpath method
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
[self.view addSubview:_internetConnectionIndicator];
// disable touch on expanded cell
UITableViewCell *cell = [self.theTableView cellForRowAtIndexPath:indexPath];
if ([[cell reuseIdentifier] isEqualToString:#"ExpandedCellIdentifier"]) {
return;
}
// deselect row
[tableView deselectRowAtIndexPath:indexPath
animated:NO];
// get the actual index path
indexPath = [self actualIndexPathForTappedIndexPath:indexPath];
// save the expanded cell to delete it later
NSIndexPath *theExpandedIndexPath = self.expandedIndexPath;
// same row tapped twice - get rid of the expanded cell
if ([indexPath isEqual:self.expandingIndexPath]) {
self.expandingIndexPath = nil;
self.expandedIndexPath = nil;
}
// add the expanded cell
else {
self.expandingIndexPath = indexPath;
self.expandedIndexPath = [NSIndexPath indexPathForRow:[indexPath row] + 1
inSection:[indexPath section]];
}
[tableView beginUpdates];
if (theExpandedIndexPath) {
[theTableView deleteRowsAtIndexPaths:#[theExpandedIndexPath]
withRowAnimation:UITableViewRowAnimationNone];
}
if (self.expandedIndexPath) {
[theTableView insertRowsAtIndexPaths:#[self.expandedIndexPath]
withRowAnimation:UITableViewRowAnimationNone];
}
[tableView endUpdates];
// scroll to the expanded cell
[self.theTableView scrollToRowAtIndexPath:indexPath
atScrollPosition:UITableViewScrollPositionMiddle
animated:YES];
}
- (NSIndexPath *)actualIndexPathForTappedIndexPath:(NSIndexPath *)indexPath
{
if (self.expandedIndexPath && [indexPath row] > [self.expandedIndexPath row]) {
return [NSIndexPath indexPathForRow:[indexPath row] - 1
inSection:[indexPath section]];
}
return indexPath;
}
#pragma mark - UIScrollViewdelegate methods
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
for (FSParallaxTableViewCell *cell in self.theTableView.visibleCells) {
[self updateImageViewCellOffset:cell];
}
}
#pragma mark - UITableViewDelegate
- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
[self updateImageViewCellOffset:(FSParallaxTableViewCell *)cell];
}
Please help me debugging my code. Thanks here is error msg
*** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSArrayM objectAtIndex:]: index 6 beyond bounds [0 .. 5]'

Answer 1

try this,
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
FSParallaxTableViewCell *cell = nil;
static NSString *cellIdentifier = nil;
// init expanded cell
if (indexPath.row >= [rssOutputData count])
cellIdentifier = #"ExpandedCellIdentifier";
}
// init expanding cell
else {
cellIdentifier = #"Cell";
}
cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier forIndexPath:indexPath];
if (cell == nil) {
cell = [[FSParallaxTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
cell.cellImageView.image = [UIImage imageNamed:#"placeholder.png"];
}
if (indexPath.row >= [rssOutputData count]){
cell.playIconBig = [UIButton buttonWithType:UIButtonTypeRoundedRect];
cell.playIconBig.tag= indexPath.row-1;
[cell.playIconBig addTarget:self action:#selector(play:) forControlEvents:UIControlEventTouchDown];
cell.playIconBig.frame = CGRectMake(25, 5, 25, 25);
[cell.playIconBig setBackgroundImage:[UIImage imageNamed:#"play_expand.png"] forState:UIControlStateNormal];
[cell.contentView addSubview:cell.playIconBig];
}else {
[cell.cellImageView sd_setImageWithURL:[NSURL URLWithString:[[rssOutputData objectAtIndex:indexPath.row]xmllink]] placeholderImage:[UIImage imageNamed:#"placeholder"] options:indexPath.row == 0 ? SDWebImageRefreshCached : 0];
cell.clipsToBounds = YES;
//[cell.contentView addSubview:arrowImg];
cell.song.text = [[rssOutputData objectAtIndex:indexPath.row]xmltitle];
cell.artist.text = [NSString stringWithFormat:#"By %#",[[rssOutputData objectAtIndex:indexPath.row]xmlsinger]];
cell.share.text = [[rssOutputData objectAtIndex:indexPath.row]xmllikes];
cell.download.text = [[rssOutputData objectAtIndex:indexPath.row]xmldownloads];
}
return cell;
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
// take expanded cell into account when returning number of rows
if (self.expandedIndexPath) {
return [rssOutputData count] + 1;
}
return [rssOutputData count];
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
if ([indexPath isEqual:self.expandedIndexPath])
{
return 40;//height for expanded
} else {
return 140;//height for normal
}
}

Answer 2

I'm quite sure that the method tableView:numberOfRowsInSection: returns the wrong number, it returns the number that bigger than the data size. Please check carefully these lines of code:
if (self.expandedIndexPath) {
return [rssOutputData count] + 1;
}
Assure that the condition of the if statement is correct. There is a case that you have modified the data else where but you don't know about that.

Answer 3

If you are returning number of rows after adding +1 to the data source than
if (self.expandedIndexPath) {
return [rssOutputData count] + 1;
}
you should ensure that for the additional row you should not access the modal / rssOutputData should be accessed till it bounds. If in case some how the code accesses the rssOutputData for the index for which the data doesn't exist than you should be ready to see error as below
*** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSArrayM objectAtIndex:]: index 6 beyond bounds [0 .. 5]'
Please re manipulate your code it's somehow trying to access the array out of bounds.