UIPopoverController dealloc getting called—ARC environment

问题

While displaying a popover controller for a second time (after dismissing it and then re-displaying it), I get the following error:

Terminating app due to uncaught exception 'NSGenericException', reason: '-[UIPopoverController dealloc] reached while popover is still visible.'

The stack trace is only a bunch of hex and the SIGABRT happens at UIApplicationMain every time. Here's the code that the button triggers:

- (IBAction)createNewScore:(id)sender {
    if (self.pc)
        if (self.pc.popoverVisible)
            return;
        else
        // Breakpoint is hit here—crashes after this line
            [self.pc presentPopoverFromBarButtonItem:(UIBarButtonItem *)sender permittedArrowDirections:UIPopoverArrowDirectionUp animated:YES];
    NGDocumentInfoViewController *documentInfoVC = [[NGDocumentInfoViewController alloc] initWithBlankDocumentTargetInManagedObjectContext:self.context];
    UINavigationController *navc = [[UINavigationController alloc] initWithRootViewController:documentInfoVC];
    UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(doneCreatingNewScore:)];
    UIBarButtonItem *cancelButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCancel target:self action:@selector(cancelCreatingNewScore:)];
    navc.navigationBar.topItem.leftBarButtonItem = doneButton;
    navc.navigationBar.topItem.rightBarButtonItem = cancelButton;
    CGSize popoverSize = CGSizeMake(documentInfoVC.view.bounds.size.width, documentInfoVC.view.bounds.size.height);
    documentInfoVC.contentSizeForViewInPopover = popoverSize;
    UIPopoverController *popover = [[UIPopoverController alloc] initWithContentViewController:navc];
    popover.delegate = self;
    self.pc = popover;
    [popover presentPopoverFromBarButtonItem:(UIBarButtonItem *)sender permittedArrowDirections:UIPopoverArrowDirectionUp animated:YES];
}

I'd like to just retain the popover which would fix the issue, but this is an ARC environment so I don't have retain. Is there a way for me to fix the error (without turning off ARC for the file and having to manually do the memory for the entire file)?

Edit: The popover is stored as an ivar:

@property (strong) UIPopoverController *pc;

---

Does anyone have a solution for this problem (maybe an ARC override)? I'll file a BR as CodaFi suggests, but a solution would still be nice, as this is a roadblock in a major project. If this is not possible, then I suppose I'll roll my own.

回答1:

I have run into the same problem and fixed it by retaining the popover controller in a strong instance variable as suggested AND explicitly dismissing it before resetting the property with the new popover controller allocated in in the second run of the action. In your example, you should add something like this:

- (IBAction)createNewScore:(id)sender {
    if (self.pc) {
         [self.pc dismissPopoverAnimated:YES];
    }

回答2:

If your popover is stored as strong reference, it can't be deallocated. The only possibility when it can be deallocated is in the situation when the object containing the strong reference (self in your example) is also deallocated.

I think the important question is what are you doing with your views when the popover is visible.

If you have already checked this, than it must be a framework bug.

来源：https://stackoverflow.com/questions/7935140/uipopovercontroller-dealloc-getting-called-arc-environment