Remove “add another” in Django admin screen

Question

Whenever I\'m editing object A with a foreign key to object B, a plus option \"add another\" is available next to the choices of object B. How do I remove that option?

Answer 1

Based on cethegeek answer I made this:

class SomeAdmin(admin.ModelAdmin):
    form = SomeForm

    def formfield_for_dbfield(self, db_field, **kwargs):
        formfield = super(SomeAdmin, self).formfield_for_dbfield(db_field, **kwargs)
        if db_field.name == 'some_m2m_field':
            request = kwargs.pop("request", None)
            formfield = self.formfield_for_manytomany(db_field, request, **kwargs)  # for foreignkey: .formfield_for_foreignkey
            wrapper_kwargs = {'can_add_related': False, 'can_change_related': False, 'can_delete_related': False}
            formfield.widget = admin.widgets.RelatedFieldWidgetWrapper(
                formfield.widget, db_field.remote_field, self.admin_site, **wrapper_kwargs
            )
        return formfield