> I'd like to key-value observe a property of an NSManagedObject. I
> tried to register an observer (in the init: method of my app's
> controller) using "addObserver:forKeyPath:options:" but it doesn't
> work because the observation is lost as my object gets dealloc'ed soon
> after I register as an observer.
If you want the object to last, why don't you -retain it ?
Typically, if the object is in a collection managed by an array
controller, the controller does this.
> This is specified in the Core Data
> documentation : "Core Data "owns" the life-cycle of managed objects.
> [...] managed objects can be instantiated, destroyed, and resurrected
> by the framework as it requires."
This is true, but managed objects still conform to the API
requirements of NSObject. If you call -retain on it, it's not going
away. If you use retain/autorelease, it'll be in the autorelease
pool just like any other object.
This piece of the documentation is intended to dispel assumptions
about what happens after the retain count hits 0, or if any object is
fetched repeatedly, or the existence or destruction of managed
objects you did not explicitly fetch.
For thread safety and performance, the framework reserves the right
to behave strangely when you're not looking. For example, -dealloc
might be called asynchronously following the last call to -release.
There's nothing in the API of NSObject that states -dealloc must be
called immediately from within -release, but a lot of developers
assume that since most objects work that way.
--
-Ben
