Django-nonrel form field for ListField

Question

I\'m experimenting with django-nonrel on appengine and trying to use a djangotoolbox.fields.ListField to implement a many-to-many relation. As I re

Answer 1

OK, here is what I did to get this all working ... I'll start from the beginning

This is what what my model looked like

class MyClass(models.Model):
    field = ListField(models.ForeignKey(AnotherClass))

I wanted to be able to use the admin interface to create/edit instances of this model using a multiple select widget for the list field. Therefore, I created some custom classes as follows

class ModelListField(ListField):
    def formfield(self, **kwargs):
        return FormListField(**kwargs)

class ListFieldWidget(SelectMultiple):
    pass

class FormListField(MultipleChoiceField):
    """
    This is a custom form field that can display a ModelListField as a Multiple Select GUI element.
    """
    widget = ListFieldWidget

    def clean(self, value):
        #TODO: clean your data in whatever way is correct in your case and return cleaned data instead of just the value
        return value

These classes allow the listfield to be used in the admin. Then I created a form to use in the admin site

class MyClassForm(ModelForm):
    def __init__(self, *args, **kwargs):
        super(MyClasstForm,self).__init__(*args, **kwargs)
        self.fields['field'].widget.choices = [(i.pk, i) for i in AnotherClass.objects.all()]
        if self.instance.pk:
            self.fields['field'].initial = self.instance.field

    class Meta:
        model = MyClass

After having done this I created a admin model and registered it with the admin site

class MyClassAdmin(admin.ModelAdmin):
    form = MyClassForm

    def __init__(self, model, admin_site):
        super(MyClassAdmin,self).__init__(model, admin_site)

admin.site.register(MyClass, MyClassAdmin)

This is now working in my code. Keep in mind that this approach might not at all be well suited for google_appengine as I am not very adept at how it works and it might create inefficient queries an such.