If your data store is SQLite, I believe the problem is the subclass FooSub.
Since FooSub is a subclass of Foo, CoreData combines both Foo and FooSub into a single table whose columns include all properties from Foo AND FooSub. Consequently, when you create a new instance of Foo, columns from FooSub may contain invalid data. You can easily verify this by opening your SQLite database store with SQLite Database Browser, found at: http://sqlitebrowser.sourceforge.net For a solution, rework your schema to subclass FooSub directly from NSManagedObject. On Sep 29, 2010, at 9:28 AM, Gideon King wrote: > Hi, I have a bidirectional one to one relationship between two entities like > this: > > Foo <-> Bar, and Foo has a subclass FooSub. All entities are concrete. > > Sometimes when I set the inverse relationship it's like this aBar.toFoo = > aFoo, and this works fine, but when it's linking back to the subclass, > aBar.toFoo = aFooSub, it fails with a validation error: toFoo is not valid, > dangling reference to an invalid object = null. > > I would have thought it would be OK for the relationship to point to an > instance of FooSub shouldn't it? After all, it is a subclass of Foo. Or do > things work differently for subclasses in Core Data? If so, how should I work > around this problem? _______________________________________________ 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
