Question

I’m trying to write an inline editor for a specific type I’m writing. My types look like this:

class Person(models.Model):
    first_name = models.CharField(max_length=30)
    last_name = models.CharField(max_length=30)

class Donor(models.Model):
    # a donor _is_ a person
    person = models.OneToOneField("Person")

The goal is to be able to edit the information stored in Person from a Donor, as Person is more of an abstract type (though not entirely). Here’s my admin:

class PersonInline(admin.StackedInline):
    model = Person
    fields = ('first_name', 'last_name')

class DonorAdmin(admin.ModelAdmin):
    inlines = (PersonInline,)

admin.site.register(Donor, DonorAdmin)

Unfortunately, when I go to create a new Donor in the admin site, I see the following error:

Exception at /core/donor/add/
<class 'core.models.Person'> has no ForeignKey to <class 'core.models.Donor'>

Odd. Why isn’t it working with my very simple inline?

---

EDIT

I’ve found that it works if I change the location of the references to be on the Person class rather than on the Donor, but this really fouls up my design:

class Person(models.Model):
    first_name = models.CharField(max_length=30)
    last_name = models.CharField(max_length=30)
    donor = models.OneToOneField("Donor", blank=True, null=True)
    recipient = models.OneToOneField("Recipient", blank=True, null=True)
    recipient_dependant = models.OneToOneField("RecipientDependant", blank=True, null=True)

class Donor(models.Model):
    pass

class Recipient(models.Model):
    pass

class RecipientDependant(models.Model):
    pass

This seems kind of backwards to me, because a Donor is a/owns a Person object, but a Person is not/does not own a Donor. Plus, this is a bit crazy. The Person class doesn’t need to know necessarily what owns it at all.

Answer 1

You can’t have an inline for Person, but have the relationship owner (where the OneToOne field is) be the donor.

In your case, you would need a DonorInline and a PersonAdmin.