dequeueReusableCell causing weird behavior - ios

Question

i'am creating an iOS application which is similar to bbc application
- I have a table view which has two section
- 1st section contains cells containing scrollview wid images
- 2nd section contains expandable cells which contains scrollview did images
so the problem is that
when i use the dequereusable its showing weird behaviors like when the bottommost cell in the table is expanded the first cell in the first gets cleared etc etc
so i have just stopped using the queue and everything started working fine
but now when i added images after scrolling the cells which is not in the view gets refreshed and its
taking a lot of time to load
so could kindly guide me how to use the queue wisely in the code
described below
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSString *CellIdentifier=#"cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell== nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:#"hai"] autorelease];
///[here a different name has been used for the reuse identifier];////
if ([self tableView:tableView inSection2:indexPath.section]) {
Coffee *co =[appDelegate.coffeeArray2 objectAtIndex:indexPath.section-s1Count-1];
cell.textLabel.text=co.coffeeName;
}
if ([self tableView:tableView inSection1:indexPath.section]) {
Coffee *co =[appDelegate.coffeeArray1 objectAtIndex:indexPath.section];
cell.textLabel.text = co.coffeeName;
CGRect cellname = CGRectMake(5, 0, 290, 25);
UILabel *cellabel = [[[UILabel alloc] initWithFrame:cellname] autorelease];
cellabel.backgroundColor = [UIColor whiteColor];
cellabel.font = [UIFont italicSystemFontOfSize:20];
cellabel.textColor=[UIColor blueColor];
cellabel.highlightedTextColor = [UIColor clearColor];
cellabel.text=co.coffeeName;
[cell.contentView addSubview:cellabel];
}
// Configure the cell...
if ([self tableView:tableView canCollapseSection:indexPath.section])
{
if (!indexPath.row)
{
// first row
// only top row showing
if ([expandedSections containsIndex:indexPath.section])
{
cell.accessoryView = [myuicontroller accessoryWithColor:[UIColor grayColor] type:DTCustomColoredAccessoryTypeUp];
}
else
{
cell.accessoryView = [myuicontroller accessoryWithColor:[UIColor grayColor] type:DTCustomColoredAccessoryTypeDown];
}
}
else
{
// all other rows
cell.accessoryView = nil;
cell.accessoryType =UITableViewCellAccessoryDisclosureIndicator;
CGRect cellname = CGRectMake(5, 0, 290, 25);
UILabel *cellabel = [[[UILabel alloc] initWithFrame:cellname] autorelease];
cellabel.backgroundColor = [UIColor whiteColor];
cellabel.font = [UIFont italicSystemFontOfSize:13];
cellabel.textColor=[UIColor blueColor];
cellabel.highlightedTextColor = [UIColor clearColor];
// cellabel.text =[NSString stringWithFormat:#"category"];
[cell.contentView addSubview:cellabel];
myscrollView *svb;
svb=[[myscrollView alloc]initwitharray:appDelegate.newscat1];
}else{
myscrollView *s;
NSLog(#"inside the textlabel ext%#",cell.textLabel.text);
NSLog(#"count of array %d",[appDelegate.newscat1 count]);
NSString *cat=cell.textLabel.text;
[cell.contentView addSubview:s];
}
}
return cell;
}

Answer 1

You need to set the alternative reuse identifier before you dequeue the cell. At the moment you are dequeuing a cell with identifier "cell" regardless of the section you are in, so you will often be returning a section 0 cell for a section 1 part of the table.
So, branch your code so that you do different things depending on the value of indexPath.section:
if (indexPath.section == 0)
cellIdentifier = #"thisCell";
else
cellIdentifier = #"otherCell";
Then dequeue your cell, if it is nil, create with the same cell identifier variable above.
You should only be adding subviews inside your (cell = nil) code - otherwise you will end up with cells with lots of overlapping subviews and will be wasting memory. If a cell has been dequeued, you just configure the existing subviews, you don't make new ones. You can assign tags to your subviews as you add them to assist with this.