On Fri, Aug 29, 2008 at 10:56 AM, Dave Dribin <[EMAIL PROTECTED]> wrote: > Hi all, > > It seems that KVO best practice is to use the "context" in > observeValueForKeyPath:ofObject:change:context: to differentiate between > different key paths, rather than check key path strings for equality. Since > context is a void *, it also seems best practice to just use some unique > pointer values. For example, mmalc's Graphics Bindings sample does this: > > static void *PropertyObservationContext = (void *)1091; > static void *GraphicsObservationContext = (void *)1092; > static void *SelectionIndexesObservationContext = (void *)1093; > > I'm not quite understanding the point of using number values like this, > though. Won't using unique string literals (char * or NSString *) also > work?
This (void *)1091 business seems highly dangerous to me. After all, what prevents somebody else from using 1091 too? If everybody uses a pointer value that's guaranteed to be unique (like a unique string literal) then you know you're safe. Mike _______________________________________________ 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: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to [EMAIL PROTECTED]
