我可以为 model formset 使用标准通用 CreateView 吗？

Question

I am again stuck with model formset. I have following form:

ArticleFormSet = modelformset_factory(Article, fields=('title', 'pub_date'), extra=3)

and View for this model formset:

class ArticleCreateView(CreateView):
   model = Article
   form_class = ArticleFormSet
   template_name = 'article_form_view.html'
   success_url = "/"

Reading documentation here: https://docs.djangoproject.com/en/4.0/topics/forms/modelforms/#model-formsets I understand that, I can use ArticleFormSet instead of standard form for form_class attribute.

So basically, what I am expecting is, this should display 3 forms for the same Article model and I should be able to create three articles at the same time.

But I am getting "TypeError: init () got an unexpected keyword argument 'instance' ".

So the question is, is this how it supposed to work? Or what would be the correct way of creating few articles at the same time?

Answer 1

I do not think that the generic CreateView is by default capable of handling formsets; however, it should be easier to customize the view so it works as you intend.

From what I see the exception is raised when the view tries to create the form to render. So overriding the get_form method is required:

class ArticleCreateView(CreateView):

...

   def get_form(self):
        if self.request.method == 'POST':
            return self.form_class(self.request.POST)

        return self.form_class()

The method either returns the modelformset as created by the factory (in case of calling the formset) or fills it with your posted data.

One more issue seems to be the success_url. You will get an expception when you use a formset. So you also need to override that method, eg

...
    def get_success_url(self):
        return self.success_url 

Now it should work.

However: If I understand you correctly, you want the view to be used for creating new data. The `` modelformset_factory``` fetches all your model instance and appends 3 empty forms. This might not be what you want. In order to get an empty formset look at this SO post:

Empty ModelFormset in Django's FormWizard