Django: How to add an extra form to a formset after it has been constructed?

Question

This is roughly what I\'m trying to do:

def post(request):
    VehicleFormSet = formset_factory(StaffVehicleForm)
    if request.method == \'POST\':
        vehi         


        

Answer 1

class RequiredFormSet(BaseFormSet):
    def add_form(self, **kwargs):
        # add the form
        tfc = self.total_form_count()
        self.forms.append(self._construct_form(tfc, **kwargs))
        self.forms[tfc].is_bound = False

        # make data mutable
        self.data = self.data.copy()

        # increase hidden form counts
        total_count_name = '%s-%s' % (self.management_form.prefix, TOTAL_FORM_COUNT)
        initial_count_name = '%s-%s' % (self.management_form.prefix, INITIAL_FORM_COUNT)
        self.data[total_count_name] = self.management_form.cleaned_data[TOTAL_FORM_COUNT] + 1
        self.data[initial_count_name] = self.management_form.cleaned_data[INITIAL_FORM_COUNT] + 1

    def add_fields(self, form, index):
        super(RequiredFormSet, self).add_fields(form, index)
        form.empty_permitted = False

That will do it. Only took 7 hours to figure out. And I still don't know why I need .is_bound = False to make the initial values not screw up.