> On Sep 21, 2016, at 8:00 PM, Slipp Douglas Thompson > <apple+cocoa-...@slippyd.com> wrote: > >> On Sep 21, 2016, at 17:01 , Graham Cox <graham....@bigpond.com> wrote: >>> >>> This should be: if([(NSString*)context >>> isEqualToString:@“mediaLibraryLoaded”])… >> >> Actually, this is not a good idea either, because *other* observations — >> ones you don’t control — might use a value that’s not an object, or not even >> a valid pointer. >
I see your point about context plausibly not being neither an NSObject nor nil. While you could check if context is an NSObject beforehand (is there even a reliable way to do this? CocoaWithLove <http://www.cocoawithlove.com/2010/10/testing-if-arbitrary-pointer-is-valid.html> couldn't find a great approach ;-/)— I think coding consistently against all other addObserver: calls in your app is a good-enough solution. I.E. If you implement observeValueForKeyPath: with [context isEqual: …] checks, make sure all the other addObserver: calls (for those same keys, at least) are using nil or NSObjects. Thoughts? — Slipp _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) 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: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
