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POCore Data returns NSManagedObject instead of Concrete class, but only when using . accessor
 

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    <p>I have set up a Core Data model where I have two objects, say Person and Address. A person has an address, and an address can belong to many people. I have modelled it in core data as such (so the double arrow points to Person, while the single arrow goes to Address)</p> <p>I have then created two classes for those objects, and implemented some custom methods in those classes. In the Core Data model I have entered the names of the classes into them.</p> <p>If I fetch an Address from Core Data directly, it gives me the actual concrete class and I can call my custom methods on it. </p> <p>If on the other hand I fetch a Person and try to access the Address through Person (eg: person.address) I get back an NSManagedObject that is an address (eg: I can get to all the core data attributes I've set on it) but it doesn't respond to my custom methods, because it's of type NSManagedObject instead of Address. Is this a limitation of Core Data or am I doing something wrong? If it is a limitation are there any work arounds?</p>
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    1. COIt's not a Core Data limitation; you are certainly doing something wrong. What exactly do you mean by "it doesn't respond to my custom methods, because it's of type NSManagedObject instead of Address"? Do you get a selector not recognized exception? Does the compiler complain? Show us some code and output or it will be hard to diagnose the problem.
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    2. COSo it's a runtime error (not a compiler one), about NSManagedObject not responding to the name of my custom method. The same error you get when you don't specify the name of your class in the core data modeller.
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