Why we are checking if (cell == nil) in UITableViewController?

Question

I am trying to implement UITableView based Application.For that I select UITableViewStyle is Group.In my TableView their is 15 section each section having 1

Answer 1

The test if (cell == nil) handles the case where there are no reusable cells to dequeue, in which case you must create a new cell. When you create the new cell, you are responsible for constructing its view hierarchy.

Answer 2

NSString *CellIdentifier = [NSString stringWithFormat:@"%i",indexPath.row];

// Dequeue or create a cell of the appropriate type.
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

This can be used instead of

static NSString *CellIdentifier = @"Cell";

UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

this is the simple example to write inside the cell ==nill

- (UITableViewCell *)tableView:(UITableView *)tableView1 cellForRowAtIndexPath:(NSIndexPath *)indexPath {

static NSString *CellIdentifier = @"CellIdentifier";
// Dequeue or create a cell of the appropriate type.
UITableViewCell *cell = [tableView1 dequeueReusableCellWithIdentifier:CellIdentifier];
cell= nil;
if (cell == nil) 
{
    cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
    [[cell.contentView viewWithTag:100+indexPath.row] removeFromSuperview]; 

    UIView *selectview = [[UIView alloc]initWithFrame:CGRectMake(0, 0, cell.frame.size.width, 30)];
    [selectview setBackgroundColor:[UIColor colorWithPatternImage:[UIImage imageNamed:@"strip_s12A-1_h.png"]]];
    cell.selectedBackgroundView = selectview;
    [selectview release];

    UILabel *cellTitle=[[UILabel alloc]initWithFrame:CGRectMake(40, 0, 300, 30)];
    //cellTitle.adjustsFontSizeToFitWidth=YES;
    [cellTitle setBackgroundColor:[UIColor clearColor]];
    [cellTitle setFont:[UIFont fontWithName:@"Arial Rounded MT Bold" size:17]];
    [cellTitle setTextColor:[UIColor blackColor]];
    cellTitle.tag = 100+indexPath.row;

        cellTitle.text= [[[cellArray objectAtIndex:indexPath.section]objectAtIndex:indexPath.row] valueForKey:@"Des2"];

    [cell.contentView addSubview:cellTitle];

    [cellTitle release];
}
return cell;
     }

i think will be enough right