What if no reusable cell in UITableView - iphone

Question

Can anyone please tell me what is the correct way to manage UITableView if I have a big number of cells? The interface of each cell depends on sections (each cell keeps different UI elements in its content view). I do not want to use reusable cells as it messes up with overlapping.
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[CustomCell alloc] initWithStyle:UITableViewCellStyleDefault nil] autorelease];
} else {
cell = nil;
[cell release];
cell = [[[CustomCell alloc] initWithStyle:UITableViewCellStyleDefault nil] autorelease];
}

Answer 1

No, your code is not correct. First of all, it wouldn't even compile because [[CustomCell alloc] initWithStyle:UITableViewCellStyleDefault nil] is not valid syntax. Secondly, the [cell release]; line has no effect (which is good because if it had, it would be wrong) but its presence shows that you haven't understood the memory management concepts (yet).
Thirdly and most importantly, you should definitely use the table view's cell reuse, especially if you have a big table. If you have different types of cells, just use different reuse identifiers for them, no problem. The table view will then create multiple reuse pools and always return a cell of the type you ask it for in dequeueReusableCellWithIdentifier:.

Answer 2

I'm using reusable cells in my app. The method I'm using is as follows:
-(UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"CellIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
}
NSUInteger row = [indexPath row];
cell.textLabel.text = [yourArray objectAtIndex:row];
return cell;
}
It works fine.

Answer 3

Without reuseIdentfier you will run out of memory fast and tableview will scroll slow. You should change content of cells in this method, e.g. titles, images, etc. but not views. So create subclasses of cell for every section you need. Setup their views and in this method setup content.
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[CustomCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:CellIdentifier] autorelease];
} else {
cell.title = [_cellTitles objectAtIndex:indexPath.row];
cell.image = [_cellImages objectAtIndex:indexPath.section];
}