Hello all, In my Core Data based application, I have an NSArrayController, and it was necessary for me to receive a KVO notification when either a new item was added to the array controller, or removed from the array controller. By looking in to some forums, I found out that I cannot do this by observing the arrangedObjects property in NSArrayController - some say this is a bug. So instead, I binded the contentArray to a mutable array that I used to add and removed objects to or from. In addition, I added array accessors for the mutable array so that the KVO would work as expected. This now works beautifully, and I receive KVO notifications for object insertion and removal, as well as have the ability to see which objects were added or removed when observeValueForKeyPath:ofObject:change:context: is invoked.
However, in doing this, I lost some of the functionality that came for free with Core Data: undo/redo, load/save, etc. I suppose this is because Core Data makes the changes to arrangedObjects (and the mutable array binded to contentArray is not touched), and I am no longer observing arrangedObjects. I manually added some undo/redo functionality in the array accessors, but now thinking about how to do loading documents. I would like to stay away from observing arrangedObjects, as then I would receive two KVO notifications for adding and removing objects in to the NSArrayController (one through the contentArray observation and one through the arrangedObjects observation). I also thought about subclassing NSArrayController so that addObject: performs a KVO notifications like so: [self willChange:NSKeyValueChangeInsertion valuesAtIndexes:indexes forKey:@"arrangedObjects"]; [super addObject:object]; [self didChange:NSKeyValueChangeInsertion valuesAtIndexes:indexes forKey:@"arrangedObjects"]; This would alleviate the need to use the contentArray property. However, I am assuming this would generate two KVO events - the new insertion notification (NSKeyValueChangeInsertion), and the existing change notification (NSKeyValueChangeSetting). I would like to avoid this. So my question is, is there an easy and efficient way to achieve what I am trying to do? Thank you in advance. Ajay _______________________________________________ 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 arch...@mail-archive.com
