Question

I tried the following code, but the cell doesn’t change at all:

- (void)viewDidLoad
{
    [super viewDidLoad];

    //Set background image of cells
    UITableViewCell *cell;

    cell = [CalculatorTableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:0 inSection:0]];
    cell.backgroundView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"Spots.png"]];

}

Answer 1

Two things. First of all, cells should be created in the cellForRowAtIndexPath method. Secondly, you should make your background view and then add it to the cell content view.

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
   cell = [CalculatorTableView alloc] initWithStyle:UITableViewStyleDefault reuseIdentifier:nil]; //This wil obviously depend on your subclass
   UIImageView *backgroundView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"Spots.png"]];
   [cell.contentView addSubview:backgroundView];
}