ios7 NSInvalidArgumentException presenting UIPopoverController

Question

Trying to show a UIPopoverController crashes in ios 7 while it works in ios6 and before. The error message is

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIPopoverController _commonPresentPopoverFromRect:inView:permittedArrowDirections:animated:]: Popovers cannot be presented from a view which does not have a window.'

In fact, it's true: self.view.window is nil in ios7 but not in ios6.

The code:

UIPopoverController *pop = [[UIPopoverController alloc] initWithContentViewController:aViewCtl];
pop.delegate = self;
[pop presentPopoverFromRect:CGRectMake(aRect inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];

The view is created (and assigned to self.view) programatically in the loadView method, while the popover is shown after pressing a button. Any suggestion?

EDIT: looks like the problem is using a modal view before showing the popup, in spite of dismissing it. Somehow, the self.view.window is lost after presenting it.

Answer 1

The best solution I've found is to check self.view.window. If it is nil, then register a delegate in the view and wait for didMoveToWindow, which will call the delegate and proceed to create and show de popover.