Question

I have an NSManagedObject subclass and wish to fetch one of its child objects given a certain value which is a property of the child “position”.

I have written a function - (ChildObject*)childWithPosition:(int)position.

Inside here I check if that child exists and return it if it does.

If it doesn’t exist then I want to create it.

So…

Can I do this inside the ParentObject…

- (ChildObject*)childWithPosition:(int)position
{
    //check if child exists and return it if it does.
    // if it does not exist then...

    ChildObject *child = [[ChildObject alloc] initWithEntity:[NSEntityDescription entityForName:@"ChildObject" inManagedObjectContext:self.managedObjectContext] insertIntoManagedObjectContext:self.managedObjectContext];

    child.position = position;

    return child;
}

My question is, is it OK and safe to use the property self.manageObjectContext on the parent and use this context to insert a new child object?

Answer 1

Yes. But why don’t use managedObjectContext property of NSManagedObject?

From Apple docs:

managedObjectContext Returns the managed object context with which the
receiver is registered.

So, for example:

NSManagedObjectContext* currentContext = parent.managedObjectContext;