Question

What is the best way to write a class based view that both shows a date-based object and a form? The use case is a site index page view that both displays today’s object and has a contact form.

At first I thought of using TodayArchiveView and ContactFormView as mixins for my site index page view. However, TodayArchiveView inherits from BaseDateListView, and ContactFormView inherits from ProcessFormView. Both ProcessFormView and BaseDateListView implement get() and ultimately call render_to_response with very different data, so I’m thinking this won’t work because even if I could call both through super, which would be returned? (I’m not even sure my thinking on this is correct; I’m still wrapping my head around multi-inheritance.)

Then I thought of writing my own get() that combines the functionality of the two gets, since their functionality doesn’t collide, as far as I can tell. So that ended up looking like:

def get(self, request, *args, **kwargs):
    form_class = self.get_form_class()
    form = self.get_form(form_class)

    self.date_list, self.object_list, extra_context = self.get_dated_items()
    context = self.get_context_data(form=form, object_list=self.object_list,
        date_list=self.date_list)
    context.update(extra_context)
    return self.render_to_response(context)

Is this the right approach?

As a larger question, how do you know which mixins can be used with each other? I had to go to the django source to realize that both classes were implementing get().

Answer 1

Is your form related to the object or not? From the description it seems it isn’t, and I’m guessing that your contact form is in some kind of a sidebar or a similar site-wide (or at least a section-wide) element.

If that is correct I wouldn’t include the form in the view at all; instead, I would use a tag or an include or a similar method to place a separately-defined template.