Navigation and MapKit makes app crash

Question

I have an application which used top bar navigation and a MapView. On the map view I have placed some annotations and when selecting an annotation, pressing the disclosure button to go into a subview and then going back to the MapView using the back button my application crashes. It does not give me any errors.

Can anyone help me figure out why my application keeps crashing?

I have made a short video showing this mysterious crash (because I'm afraid that I do not explain it very well)

The video can be seen on this link http://snuzzer.dk/pub/iPhoneAppMapKitCrash.mov

Please tell me if you need to see any code in order to determine the reason for the crash. I am not sure what code would be necessary for this as I do not get any error.

EDIT: This is the output of my stack trace:

#0  0x01275a63 in objc_msgSend
#1  0x0586c860 in ??
#2  0x0037ef1d in -[UINavigationController setDisappearingViewController:]
#3  0x0037c4f6 in -[UINavigationController _clearLastOperation]
#4  0x0037ce3f in -[UINavigationController navigationTransitionView:didEndTransition:fromView:toView:]
#5  0x00509e23 in -[UINavigationTransitionView _notifyDelegateTransitionDidStopWithContext:]
#6  0x0050afd2 in -[UINavigationTransitionView _cleanupTransition]
#7  0x002f6665 in -[UIViewAnimationState sendDelegateAnimationDidStop:finished:]
#8  0x002f64f7 in -[UIViewAnimationState animationDidStop:finished:]
#9  0x01ffa6cb in run_animation_callbacks
#10 0x01ffa589 in CA::timer_callback
#11 0x010f4fe3 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__
#12 0x010f6594 in __CFRunLoopDoTimer
#13 0x01052cc9 in __CFRunLoopRun
#14 0x01052240 in CFRunLoopRunSpecific
#15 0x01052161 in CFRunLoopRunInMode
#16 0x01a48268 in GSEventRunModal
#17 0x01a4832d in GSEventRun
#18 0x002d442e in UIApplicationMain
#19 0x00002918 in main at main.m:14

EDIT: It seems that when I do not release my annotationViewController the application does not crash. I will keep playing with the application to see if this is right. Can anyone tell me if this might be right and if so, why? And when would I release it then?

 - (void)mapView:(MKMapView *)aMapView annotationView:(MKAnnotationView *)view calloutAccessoryControlTapped:(UIControl *)control {
    for(MyAnnotation* a in mapView.annotations) { // searching for chosen annotation
        if(view.annotation == a) {
            // set array from plist
            NSString *path = [[NSBundle mainBundle] pathForResource:@"Annotations" ofType:@"plist"];
            NSMutableArray* anns = [[NSMutableArray alloc] initWithContentsOfFile:path];

            AnnotationDetailViewController *annotationDetailViewController = [[AnnotationDetailViewController alloc] initWithNibName:@"AnnotationDetailViewController" bundle:nil];
            annotationDetailViewController.ann = [anns objectAtIndex:[a.annId intValue]];

            [self.navigationController pushViewController:annotationDetailViewController animated:YES];
            [annotationDetailViewController release]; // this is the one that I think will correct the error
            [anns release];
        }
    }
}

Answer 1

You should look for an ivar in AnnotationDetailViewController that you are under-retaining/over-releasing. I would suspect some UIView, perhaps an IBOutlet that you did not configure to retain, particularly if you also fail to set it to nil in viewDidUnload . I recommend you read Memory Management of Nib Objects if you haven't already.

It's difficult to debug this without the code, or more information about your variables, but that's where I would look given where it's crashing.