django-admin: Add extra row with totals

Yes, you can do it in many ways, but most django-ist way to do is:

First override the default django listing view… And give a new template file directory

ModelAdmin.changelist_view(self, request, extra_context=None)

Like:

class MyModelAdmin(admin.ModelAdmin):

    # A template for a very customized change view:
    change_list_template="admin/myapp/extras/sometemplate_change_form.html"

    def get_total(self):
        #functions to calculate whatever you want...
        total = YourModel.objects.all().aggregate(tot=Sum('total'))['tot']
        return total

    def changelist_view(self, request, extra_context=None):
        my_context = {
            'total': self.get_total(),
        }
        return super(MyModelAdmin, self).changelist_view(request,
            extra_context=my_context)

So, you add your list view context a ‘total’ that keeps your total value and pass it to the template.

if change_list_template will set, django uses that template, otherwise, it uses standard django template.

If def changelist_view(self, request, extra_context=None) is called, django uses that function to create the content, otherwise it uses default django views.

Then create a admin/myapp/extras/sometemplate_change_form.html file and place your {{total}} to any place you want.

A guide to how to override admin templates
And here is how to override admin views

UPDATE: I add a simple aggregate to calculate total. you can edit it to set it as your needs.

UPDATE 2: ModelAdmin template override option fixed from ModelAdmin.change_form_template to ModelAdmin.change_list_template. (thank you c4urself). Yes, but changing the default django admin template is a really bad choice, since it is used by many other ModelAdmin’s and it might cause problems if related templates are updated.

NB:
The Total doesn’t change when using filters, see comment below.