UIView addSubview nor working in UITableViewCell - objective-c

Question

barView I have a Table View and, in each cell, I want to draw some statistic bars. I have an empty UIView created in my custom cell, its name is mainView and it is the view where the chart is drawn.
In cellForRowAtIndexPath I'm doing this:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"CustomCellIdentifier";
CustomCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
CGRect barRect = CGRectMake(0, 0, 100, 10);
UIView *barView = [[UIView alloc] initWithFrame:barRect];
[barView setBackgroundColor:[UIColor redColor]];
[cell.mainView addSubview:barView];
return cell;
}
The barView is not displaying on loading. It only shows after I change and return from another tab or after the cell goes out of the screen.
Notes:
I have tried [cell.mainView setNeedsDisplay];
I have a header made with another custom cell.

Answer 1

Try this:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"CustomCellIdentifier";
CustomCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
if (!cell) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
CGRect barRect = CGRectMake(0, 0, 100, 10);
UIView *barView = [[UIView alloc] initWithFrame:barRect];
[barView setBackgroundColor:[UIColor redColor]];
[cell addSubview:barView]; // use cell.mainView if you have that created somewhere other than here (like IB)
}
return cell;
}
dequeueResuable... can return a nil cell. So you need to have a check, to see if you should alloc/init a new cell. In the code I gave you if dequeueResuable... returns you a proper cell then it would have been created with the subview intact already. So no need to re-add it (hence creating it only in if (!cell))

Answer 2

Your description clearly indicates you are filling your barView outside this function. So that it becomes visible only after transition.
Or you are simply overwriting it (or even overwriting mainview) outside what you have provided here.
Check your viewdidload and viewdidappear and the likes.

Answer 3

I have solved it easily with:
- (void)viewDidAppear:(BOOL)animated
{
[self.tableView reloadData];
}
It seems that adding a subview cant be done before the view is created in the window, before the cells are completely loaded.