Question

I am trying to write an abstract class to manage managed entities. However, I am not that familiar with Objective-C and wonder how to do the following.

In my abstract class controller I have my ManagedObjectContext.
In my objectController (which implements the abstractController) I need to create an entity.
In the abstract class I have the following:

- (NSManagedObject *) getNewObject {
    return (NSManagedObject *)[NSEntityDescription insertNewObjectForEntityForName:_objectName inManagedObjectContext:managedObjectContext];  
}

Then in my implementation I call upon this:

MyObject* object = (MyObject) [self getNewObject];

This however gives a compiler error: “Cast to incomplete type”
(MyObject is of type NSManagedObject)

What is the best way. Should I use NSClassFromString? But how do I then define “getNewObject”, something like:

- (id) getNewObject {
    return (NSClassFromString (classname)*)[NSEntityDescription insertNewObjectForEntityForName:_objectName inManagedObjectContext:managedObjectContext];  
}

Answer 1

Castin is done as below

MyObject* object = (MyObject*) [self getNewObject];