Updateview with dynamic form_class

Question

I would like to dynamically change the form_class of an UpdateView CBV in Django 1.6.

I've tried to do this using the get_context_data(), but that didn't help since the form is already initialized. So it will need to happen during __init__, I guess. Here's what I've tried on __init__:

class UpdatePersonView(generic.UpdateView):

    model = Person
    form_class = ""

    def __init__(self, *args, **kwargs):
        super(UpdatePersonView, self).__init__(*args, **kwargs)
        person = Person.objects.get(id=self.get_object().id)
        if not person.somefield:
            self.form_class = OneFormClass
        elif person.somefield:
            self.form_class = SomeOtherFormClass

I'm stuck with a 'UpdatePersonView' object has no attribute 'kwargs' error message when executing person = Person.objects.get(id=self.get_object().id).

When manually specifying the id (e.g. id=9), then the setup works.

How can I get the args/kwargs inside the init method that I'm overriding? Particularly I would need access to the pk.

Answer 1

You should simply override get_form_class.

(Also I'm not sure why you're querying for person: that object is the same is self.get_object() already, so there's no point getting the ID of that then querying again.)

def get_form_class(self):
    if self.object.somefield:
        return OneFormClass
    else:
        return SomeOtherFormClass