• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
Re: Notifications and Subclassing
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Notifications and Subclassing


  • Subject: Re: Notifications and Subclassing
  • From: glenn andreas <email@hidden>
  • Date: Tue, 08 Mar 2011 10:07:00 -0600

On Mar 8, 2011, at 9:42 AM, Gordon Apple wrote:

> Class A:  NSObject, has methods:
>
> -  (void)foo:(Notification*)notification {
>    ...
> }
>
> - (void)addObservers {
>    [[NSNotificationCenter defaultCenter] addObserver:self
>                                             selector:@selector(foo:)
>                                                 name:notificationName
>                                               object:nil];
> }
>
>
> Class B: subclass of A.  This is the class used.
>
> Notification sent from elsewhere.  Console:
>
> -[NSCFString foo:]: unrecognized selector sent to instance 0x69807c0
>
>
> Is this due to confusion of of which class received the notification?  Or is
> this a compiler/linker bug?  I even tried declaring foo in A’s headers, to
> no avail.  This same overall procedure is used elsewhere (without
> subclassing), with no problems.  What am I missing?
>
>
>

That's a classic memory management problem.

Most likely, you're forgetting to unregister your observer when you are deallocating it (resulting in a notification center to have a stale pointer that is later reused by an NSString).


Glenn Andreas                      email@hidden
The most merciful thing in the world ... is the inability of the human mind to correlate all its contents - HPL

_______________________________________________

Cocoa-dev mailing list (email@hidden)

Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com

Help/Unsubscribe/Update your Subscription:

This email sent to email@hidden

  • Follow-Ups:
    • Re: Notifications and Subclassing
      • From: Gordon Apple <email@hidden>
References: 
 >Notifications and Subclassing (From: Gordon Apple <email@hidden>)

  • Prev by Date: Notifications and Subclassing
  • Next by Date: Re: easy way to store table-like data
  • Previous by thread: Notifications and Subclassing
  • Next by thread: Re: Notifications and Subclassing
  • Index(es):
    • Date
    • Thread