How do I filter ManyToManyField choices in a Django ModelForm?

django, django-forms, django-orm, python

Solution

def __init__(self, *args, **kwargs):
   # First pop your kwargs that may bother the parent __init__ method
   self.root_entity = kwargs.pop('root_entity')
   # Then, let the ModelForm initialize:
   super(MyForm, self).__init__(*args, **kwargs)
   # Finally, access the fields dict that was created by the super().__init__ call
   self.fields['parent_entities'].queryset = Entity.objects.filter(root_entity=self.root_entity)

Problem

I want to filter ManyToManyField choices in my ModelForm: ``` class MyForm(forms.ModelForm): class Meta: model = Entity fields = ['parent_entities'] def __init__(self, *args, **kwargs): self.root_entity = kwargs.pop('root_entity') self.Meta.fields['parent_entities'].queryset = Entity.objects.filter(root_entity=self.root_entity) super(MyForm, self).__init__(*args, **kwargs) ``` I tried a lot of different code I've seen but nothing has worked yet. I guess my problem is that I can't get this 'parent_entities' field. With this code, I have the error : ``` list indices must be integers, not str ```

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