Why does a UITableView cell.contentView.bounds.size.width change with cell reuse?

Question

I use `cell.contentView.bounds.size.width` to calculate the position of a text field in a UITableView cell. When the cell is created, debug code reports the width as 302. When the cell scrolls off the screen and then back on, the debug code reports that the it is 280--every time. It doesn't seem to want to go back to 302 and stays stuck at 280. The net result is that the text field gets put in the wrong place the second time the field is put into the cell's contentView, though it was put in the right place the first time.
I figure 22 is significant somehow, but I don't know what it is. Guessing it might be the disclosure arrow, I moved the "clear the cell" code up front of the width determination, including setting the accessory to nada.
Can anybody tell me what's going on here?
The code (with irrelevant--that I know of--stuff snipped out) looks like this:
<code>
    // Customize the appearance of table view cells.
    - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
        static NSString *CellIdentifier = @"Cell";
              NSUInteger section = [indexPath section];
              NSUInteger row = [indexPath row];
        UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
        if (cell == nil) {
            cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier] autorelease];
        // Configure the cell.
        while( [cell.contentView.subviews count] ){
            id subview = [cell.contentView.subviews objectAtIndex:0];
            [subview removeFromSuperview];
        cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
    8< snip!
              CGFloat          theCellWidth = cell.contentView.bounds.size.width - 44.0;
              CGFloat theLineHeight = [[UIFont boldSystemFontOfSize: [UIFont labelFontSize]+1.0] lineHeight];
        NSLog(@"cell.contentView.bounds.size.width %1.0f",cell.contentView.bounds.size.width);
        if (0==section) {
                        switch (row) {
                                  case 2:
                    while( [cell.contentView.subviews count] ){
                        id subview = [cell.contentView.subviews objectAtIndex:0];
                        [subview removeFromSuperview];
                    cell.selectionStyle = UITableViewCellSelectionStyleNone;
                                            cell.textLabel.text = @" ";
                                            cell.detailTextLabel.text = @"The Age";
                                            theAgeTextField.frame = CGRectMake(10.0, 2.0, theCellWidth, theLineHeight);
    //                NSLog(@"cell.contentView %@",cell.contentView);
                                            theAgeTextField.text = theAge;
                                            theAgeTextField.font = [UIFont boldSystemFontOfSize: [UIFont labelFontSize]+1.0];
                                            theAgeTextField.keyboardType = UIKeyboardTypeDecimalPad;
                                            theAgeTextField.borderStyle = UITextBorderStyleNone;
                                            theAgeTextField.userInteractionEnabled = NO;
                                            [cell.contentView addSubview:theAgeTextField];
                                            cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
                                            break;
    8< snip! (lots of closing braces and other stuff omitted)
        return cell;
<hr>
</code>
**Want to try this one at home, boys and girls?**
Start with a new Navigation-based Application. Put the following code into RootViewController.m:
<code>
    - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
        return 5;
    // Customize the appearance of table view cells.
    - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
        static NSString *CellIdentifier = @"Cell";
        UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
        if (cell == nil) {
            cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier] autorelease];
        NSLog(@"cell.contentView.bounds.size.width %1.0f",cell.contentView.bounds.size.width);
        // Configure the cell.
        return cell;
</code>
There are only two changes in the default code required to make this happen: changing the number of rows in the section ("return 5") and the style of the cell must be _UITableViewCellStyleSubtitle_. Then, when you run the program, you'll see five lines of this:
<code>
    2011-06-18 11:10:19.976 TestTableCells[7569:207] cell.contentView.bounds.size.width 302
    2011-06-18 11:10:19.978 TestTableCells[7569:207] cell.contentView.bounds.size.width 302
    2011-06-18 11:10:19.979 TestTableCells[7569:207] cell.contentView.bounds.size.width 302
    2011-06-18 11:10:19.980 TestTableCells[7569:207] cell.contentView.bounds.size.width 302
    2011-06-18 11:10:19.982 TestTableCells[7569:207] cell.contentView.bounds.size.width 302
</code>
Drag some cells off the screen (drag up--down doesn't do anything) and when they reappear, you get this:
<code>
    2011-06-18 11:10:24.013 TestTableCells[7569:207] cell.contentView.bounds.size.width 320
    2011-06-18 11:10:24.047 TestTableCells[7569:207] cell.contentView.bounds.size.width 320
    2011-06-18 11:10:24.130 TestTableCells[7569:207] cell.contentView.bounds.size.width 320
</code>
Frankly, I'm frustrated as heck with this, and am so very tempted to pony up the $99 (without a working app, even) so I can have somebody at Apple weigh in on this one.
<hr>
Wanna' see something more interesting? Try this in place of the `static NSString...` line:
<code>
        NSString *CellIdentifier = [NSString stringWithFormat: @"%d", arc4random() ];
        NSLog(@"%@",CellIdentifier);
</code>
Now, every time, the width in the log is _always_ 302. It would seem, then, that a reused cell has different content width than the original cell.
Anybody got a clue on this?

Answer 1

Hi,
i guess the reason is that a newly create cell is create with a default frame by initWithStyle:
But it's not yet added to any superview so you're logging that default size.
After returning the new cell the tableViewController adds that cell as subview to the tableView which can lead to a resize of that cell.
If the cell is scrolled off screen it's just removed from superview but stays the same size. If it's reused later it's still having the same size it had when removed from superview.
Dirk
initWithStyle:
But it's not