MKMapView still sending messages to delegate after it's superview has been de-alloc'ed

Question

EDIT: changed the title. I didn\'t know it at the time but this is a duplicate of Why am I crashing after MKMapView is freed if I'm no longer using it?

---

This q

Answer 1

MKMapView is not compiled with ARC and because of that the property for delegate is still declared as assign instead of weak.
From the MKMapView documentation:

@property(nonatomic, assign) id delegate

---

And from the Transitioning to ARC Release Notes:

You may implement a dealloc method if you need to manage resources other than releasing instance variables. You do not have to (indeed you cannot) release instance variables, but you may need to invoke [systemClassInstance setDelegate:nil] on system classes and other code that isn’t compiled using ARC.

---

For delegates of system classes (NS*, UI*) you have to use the "old" rule of setting delegates to nil when you deallocate the delegate object.

so add a dealloc method to your detailViewController

- (void)dealloc {
    self.mapView.delegate = nil;
}