[baseten-users] Dictionary for creating new objects

[Erik Aderstedt]

Hi!

When creating a new object with an entity thats on the many side of a  
one-to-many relationship, I set up a dictionary like so:

BXDatabaseObject *customer;
/* .. customer is set up .. */

NSDictionary *fieldValues = [NSDictionary dictionaryWithObjectsAndKeys:
	customer, @"customer", /* customer is the foreign key constraint, and  
"Customer" is the entity on the "one" side of the relationship */
	.. other fields ..
	,nil];

BXDatabaseObject *license =  [ctx createObjectForEntity:[ctx  
entityForTable:@"License" error:&error] withFieldValues:fieldValues  
error:&error];

With the above code the createObjectForEntity call throws an exception:
	-[NSCFDictionary setObject:forKey:]: attempt to insert nil key

No "license" object is inserted. I'm not clear on why this fails. The  
workaround is simple:

fieldValues =  [NSDictionary dictionaryWithObjectsAndKeys:
			[customer valueForKey:@"id"], @"customer_id",
			... other fields ..
			, nil];

but it feels less elegant than the first solution. Is the error due to  
a bug in BaseTen (I'm using 1.6.2) or is it just not the way to do it?  
Coming from a Core Data background, the first approach seems natural...

Cheers,
Erik Aderstedt
Aderstedt Software AB