Question

I’m using a UITableView to display custom cells created with Interface Builder. The table scrolling isn’t very smooth (it “stutters”) which leaves me to believe cells aren’t being reused. Is there something wrong with this code?

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

static NSString *CellIdentifier = @"TwitterCell";
TwitterCell *cell = (TwitterCell *)[tableView dequeueReusableCellWithIdentifier:CellIdentifier];

if (cell == nil){
    //new cell
    NSArray *topLevelObjects = [[NSBundle mainBundle] loadNibNamed:@"TwitterCell" 
                                                   owner:nil options:nil];

    for(id currentObject in topLevelObjects)
    {
        if([currentObject isKindOfClass:[TwitterCell class]])
        {
            cell = (TwitterCell *)currentObject;
            break;
        }
    }

}

if([self.tweets count] > 0) {
    cell.lblUser.text = [[self.tweets objectAtIndex:[indexPath row]] username];
    cell.lblTime.text = [[self.tweets objectAtIndex:[indexPath row]] time];
    [cell.txtText setText:[[self.tweets objectAtIndex:[indexPath row]] text]];
    [[cell imgImage] setImage:[[self.tweets objectAtIndex:[indexPath row]] image]];
} else {
    cell.txtText.text = @"Loading...";
}


cell.selectionStyle = UITableViewCellSelectionStyleNone;

return cell;
}

Answer 1

Maybe this blog entry from atebits (creators of Tweetie) can help you: http://blog.atebits.com/2008/12/fast-scrolling-in-tweetie-with-uitableview/

Cutting to the chase, here’s the secret: One custom view per table cell, and do your own drawing. Sounds simple? That’s because it is. It’s actually simpler than dealing with a ton of subviews of labels and images, and it’s about a bzillion times faster (according to my informal tests).