向 inlineformset_factory 添加额外参数

Question

After a few hours of searching I must admit that I am defeated.

I have read the Django docs but I really can't find a solution to my problem.

Consider the following line of code:

EmploymentFormSet = inlineformset_factory(Profile, Employment, form=EmploymentForm, extra=3)

This code lives in a classbased view which inherits from UpdateView and furthermore in the method get_context_data(self, *args, **kwargs):

This is pretty straight forward as the inlineformset_factory creates an EmploymentFormSet.

Now consider this

queryset = Employment.objects.filter(profile__pk=self.kwargs['pk']).values()
context['emp_formset'] = EmploymentFormSet(prefix='emp_form', initial=queryset, auto_id=True)

I thought by supplying initial=queryset , which only applies to unbound instances IIRC, it would populate my formset with as many as the queryset would contain.

So the queryset will in my case return 4 Employments but when using the extra parameter, the formset I'm constructing are only filled with as many as this parameter defines, in my example only 3 since I defined only 3 extras. Incrementing the extra will populate the forms incrementally.

I've tried subclassing the BaseInlineFormSet but I haven't really broken through the wall.

My question is how would I go about to populate the formset with as many forms as the queryset contains, I'm not really out for an exact solution but more of a pointer in the right the direction! :)

Thanks!

Answer 1

I solved it by constructing this method

def set_extra_forms(extra_forms, **kwargs):
    EmploymentFormSet = inlineformset_factory(Profile, Employment, form=EmploymentForm, extra=extra_forms)
    return EmploymentFormSet(**kwargs)

Now I do believe this is the way to go but I have to refactor the code in order to make it more dynamic right now its connected to one class and one class only but it works like a charm.

Answer 2

Define the formset inside a view

def employment_view(request, pk=None):
  #Define extra forms variable
  extra_forms = Employment.objects.filter(profile__pk=self.kwargs['pk']).count()
  #Define formset inside the view function
  EmploymentFormSet = inlineformset_factory(Profile, Employment, form=EmploymentForm, extra=extra_forms)
  #Use this in context
  context['emp_formset'] = EmploymentFormSet()