2 Replies
      Latest reply on Jul 21, 2016 1:02 PM by ObjColumnist
      zespri Level 1 Level 1 (0 points)

        I thought this would crash, but it doesn't seem to

        I have a UIViewController subclass with the following:


        - (void)viewDidLoad {
            [super viewDidLoad];
            NSNotificationCenter * nc = [NSNotificationCenter defaultCenter];
            [nc addObserver: self
                   selector: @selector(userDataChanged:)
                       name: kUserDataUpdated
                     object: nil];
        - (void) dealloc {
        - (void) userDataChanged: (NSNotification *)notif {
            [self configureWithLoggedInUser];


        a breakpoint in viewDidLoad suggests addObserver is getting called as expected

        a breakpoint in userDataChanged suggests i'm able to trigger my notification.

        a breakpoint in dealloc suggests dismissing the view/controller is working as expected.


        But I thought the next time the app posted kUserDataUpdated the app would crash.

        currently when I:

        1. load my viewController

        2. dismiss/deallocate it

        3. post kUserDataUpdated


        nothing bad is happening.


        Is it no longer necessary to call removeObserver in dealloc?

        or am I avoiding a crash because this is running in the simulator (lots of mem) and I haven't done much else between steps 2 and 3?