On Wed, 2009-03-04 at 11:44 -0800, Margie wrote: > Hi Malcolm. So after reviewing your pointers, I had high hopes of > being able to move to using the modelformset_factory, but I still seem > to have problems. The problem I run into is that when _construct_form > (the one in django/forms/models.py) is called, it tries to do this: > > if i < self._initial_form_count: > kwargs['instance'] = self.get_queryset()[i] > > I have no objects of my model yet and get_queryset() returns > self._queryset, which is []. The above [i] index then causes a 'list > index out of range exception'. I think this was what I first > encountered which made me think that I had to have a queryset to use > modelformset_factory.
That second line of code will only be executed if self._initial_form_count is greater than 0. You aren't providing any initial forms, so it should be zero. Looking at the source (it's set in the BaseFormset.__init__ method), it will only be non-zero if you supply initial data, which kind of makes sense, since providing initial data for "extra" forms would mean you'd always end up creating a new record every time you viewed and submitted that form. I can see why it's set up that way, although it confirms my wish to spend a couple of days going over the formsets documentation with a two-by-four. I think it means that supplying this tile id via initial data is probably not a great idea, as it will inadvertently create new records own the track. I'd kind of been thinking that approach might have been a little clunky, anyway, so this backs up that hunch. I'll put some more details in the formset initialization thread, because it's probably more appropriate there. Regards, Malcolm --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~----------~----~----~----~------~----~------~--~---
