Ios 7 popover does not work - ipad

Question

I am trying to update my app so that it properly works on iOs7.
in iOS 5 & 6 this worked perfectly:
if ([segue.identifier isEqualToString:#"popover"])
{
FavoritesViewController *vc = segue.destinationViewController;
CGFloat width = 200.0;
CGRect rect = [vc.tableView rectForSection:[vc.tableView numberOfSections] - 1];
CGFloat height = CGRectGetMaxY(rect);
if ([segue isKindOfClass:[UIStoryboardPopoverSegue class]])
{
_filterPopoverController = [(UIStoryboardPopoverSegue *)segue popoverController];
[_filterPopoverController setPopoverContentSize:CGSizeMake(width, height)];
[_filterPopoverController setDelegate:self];
}
}
}
I use this to check if its already on the screen
- (IBAction)touchedFilterButton:(UIBarButtonItem *)sender
{
if (_filterPopoverController == nil)
{
[self performSegueWithIdentifier:#"popover" sender:self];
}
else
{
[_filterPopoverController dismissPopoverAnimated:YES];
_filterPopoverController = nil;
}
}
if i remove this line
_filterPopoverController = [(UIStoryboardPopoverSegue *)segue popoverController];
It works but i cant set the width/height and there is no check if its on the screen.

Answer 1

The problem was iOS7 is not so "Forgiving"
i call
_filterPopoverController = [(UIStoryboardPopoverSegue *)segue popoverController];
after
CGFloat width = 200.0;
CGRect rect = [vc.tableView rectForSection:[vc.tableView numberOfSections] - 1];
CGFloat height = CGRectGetMaxY(rect);
height is always 0.000 because its not "shown" yet, so i had to replace the segue after calling the other view controller and set the width.
And i removed the subclass part because its already a subclass for sure
FavoritesViewController *vc = segue.destinationViewController;
_filterPopoverController = [(UIStoryboardPopoverSegue *)segue popoverController];
CGFloat width = 200.0;
CGRect rect = [vc.tableView rectForSection:[vc.tableView numberOfSections] - 1];
CGFloat height = CGRectGetMaxY(rect);
[_filterPopoverController setPopoverContentSize:CGSizeMake(width, height)];
[_filterPopoverController setDelegate:self];