Comments on: Runtime ChoiceField filtering in Django’s admin

By: AJ

AJ — Fri, 11 Jun 2010 19:13:40 +0000

Also you would need to assign the form and formset to the inline.

admin.py
class BilletInline(admin.StackedInline): model = Billet extra = 1 form = BilletAdminForm formset = BilletAdminFormSet

By: AJ

AJ — Fri, 11 Jun 2010 19:11:55 +0000

The only way I could think to handle a formset is to sublcass django.forms.models.BaseInlineFormSet, override the _construct_form method and pass in some an additional kwarg(the parent instance) that will then get passed to the form. So you would need to then override the __init__ method in the form and use the extra kwarg to change the queryset on the field. The pseudo code would be something like:

class BilletAdminFormSet(BaseInlineFormSet): def _construct_form(self, i, **kwargs): kwargs.update({'instance': self.instance}) return super(BilletAdminFormSet, self)._construct_form(i, **kwargs)

class BilletAdminForm(CustomModelForm): ... def __init__(self, *args, **kwargs): super(BilletAdminForm, self).__init__(*args, **kwargs) if 'instance' in kwargs and kwargs['instance']: self.fields['employees'].queryset = SomeQuerySet()

By: Andrew Wall

Andrew Wall — Mon, 22 Feb 2010 16:40:04 +0000

Thanks very much for writing about this. I’m new to both python and django and there didn’t seem to be a way to handle this kind of problem without abandoning the Admin screens from the django doc.

By: Andri Jan

Andri Jan — Mon, 03 Aug 2009 13:02:24 +0000

Yeah, that’s what I’d like to know. This is no problem with a form, it’s the formset that’s the problem

By: Jeff

Jeff — Sat, 01 Aug 2009 03:49:17 +0000

That’s a good point. How would that work with a form set, though? I didn’t see that the parent instance is passed to the form set’s constructor.

By: Ryan

Ryan — Fri, 31 Jul 2009 21:42:13 +0000

You might also do something like:

class RunTimeGameForm(forms.ModelForm):
    [...]
    def __init__(*args, **kwargs):
        super(RunTimeGameForm, self).__init__(*args, **kwargs)
        if self.instance.id:
            self.fields['home_team'].queryset=Team.objects.filter(
                sport=self.instance.season.sport)

Then there's no need to override ModelAdmin.get_formset, or have a game_form_factory function.

By: David Grant

David Grant — Fri, 31 Jul 2009 14:42:08 +0000

I did this last year…I think some guy on the mailing list gave me the code. I’m glad to see a blog post about this, because there was none at the time so it took me forever to find the solution. This is one of those things that I think a lot of people need at some point in Django development whenever the models get more complex like this and it’s not exactly obvious how to do it. Thanks!