UITableView's background color becoming white when section is empty

Question

Hi everyone.

Here is the deal: I have a UITableView with 2 sections, and I want to display a "no data" cell when the first section is empty, so that the 2 section headers are not stuck together (cause it looks weird).

It works great (even though I had trouble making it work at first, see this thread). I'm using viewForFooterInSection :

- (CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:(NSInteger)section {

if(section == 0)
{
        if([firstSectionArray count] == 0)
                return 40;
        else 
                return 0;
}

return 0;

}

- (UIView *)tableView:(UITableView *)tableView viewForFooterInSection:(NSInteger)section{

    if(section == 0)
    {
        UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(200, 10, 50, 44)];
        label.backgroundColor = [UIColor clearColor];
        label.textColor = [UIColor colorWithWhite:0.6 alpha:1.0];
        label.textAlignment = UITextAlignmentCenter;
        label.lineBreakMode = UILineBreakModeWordWrap; 
        label.numberOfLines = 0;
        label.text = @"No row";
        return [label autorelease];
    }

    return nil;
}

But the background color turns plain white when I display the section footer view. See image:

I like it better when the background is filled with empty cells. Does anyone have any idea how to do that? Thanks

Answer 1

The background is filled with empty cells when you have no footer. So do not implement a viewForFooterInSection (or titleForFooterInSection) method, and you will get the "empty cells" effect.

I'd recommend that you return a cell indicating that there are no entries to show, like so:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    if (matches.count>0) {
        // Do your usual thing here
    } else {
        static NSString *cellId = @"noDataCell";
        UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellId];
        if (cell == nil) {
            cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellId] autorelease];
            cell.textLabel.textAlignment = UITextAlignmentCenter;
            cell.textLabel.textColor = [UIColor grayColor];
        }
        cell.textLabel.text = @"Aucun match";
        return cell;
    }
}

And of course, you would have to tell UIKit that you always have at least one cell in your section... I've added the isDeletingRow case that seems to trouble you (in comment).

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    if (section==0) return matches.count>0 ? matches.count : (isDeletingRow ? 0 : 1);
    // Set 'isDeletingRow' to YES when a delete is being committed to the table, in that case we let UIKit know that we indeed took care of the delete...
    // And cover the other sections too...
}

When you are committing the edits, you need to set isDeletingRow for numberOfRowsInSection to return a satisfactory value...

- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {
    if (editingStyle == UITableViewCellEditingStyleDelete) {
        isDeletingRow = YES;
        // Your current code when a row is deleted here...
        isDeletingRow = NO;
        if (matches.count==0) [self.tableView performSelector:@selector(reloadData) withObject:nil afterDelay:0.5];
    }
}