Question

I am attempting to update a label inside a cell(note, this is NOT the cell’s label text. Its another custom label inside of the cell) after the user selects a value from a previous screen and the nav controller popping them back.

However, when I call reloadData, instead of the label in the cell being cleaned and the new value being placed, its actually stacking on top of what was there already. Like if you took the number 200 and placed a 50 on top of it. You get a weird mesh of the 0 and 5 on top of each other.

Any ideas on how to adjust this? Do I have to reset the label’s text to “” every view did appear? and if so, what’s the best way to do this, I’ve tried in the cellForRowAtIndexPath method, but no change.

cellforRowAtIndexPath code

 // Set up the cell...
static NSString *CellIdentifier = @"Cell";

UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier: CellIdentifier];
if (cell == nil) {
    cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;

    // get the dictionary object
NSDictionary *dictionary = [_groups objectAtIndex:indexPath.section];
NSArray *array = [dictionary objectForKey:@"key"];
NSString *cellValue = [array objectAtIndex:indexPath.row];
cell.textLabel.text = cellValue;

//label for currently selected/saved object
_currentSetting = [[UILabel alloc] initWithFrame:CGRectMake(160, 8, 115, 25)];
[_currentSetting setFont:[UIFont systemFontOfSize:14]];
_currentSetting.backgroundColor = [UIColor clearColor];
_currentSetting.textColor = [UIColor blueColor];
_currentSetting.textAlignment = NSTextAlignmentRight;

_currentSetting.text = [NSString stringWithFormat:@""];
_currentSetting.text = [NSString stringWithFormat:@"%@ mi",[setting.val stringValue]];

 [cell.contentView addSubview:_currentSetting];

 return cell

Answer 1

You are recreating the label and re-adding it every time the cell gets refreshed. All of your cell subviews should only be added when you create the cell the first time.

So in your code you create a cell and all subviews the first time. Then if you need a new cell for scrolling or any other reason you get a reusable cell that has already had all the subviews added to it (re-usable…). Then you go through the process of adding the subviews (again) so now that cell contains the subviews from the previous owner (data) of that cell and the new owner (data) of that cell. That is why they appear stacked on top of eachother when you reload the data.

seudo code:

(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
   UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier: CellIdentifier];
   if (cell == nil) {
      //Add all subviews here
   }

   //Modify (only modify!!) all cell subviews here

   return cell;
}