Pass initial value to a modelform in django

How can I pass an initial value for a field to a model form. I have something like the following code

class ScreeningForm(form开发者_如何学编程s.ModelForm):
    class Meta:
        model = Screening

    def __init__(self, *args, **kwargs):
        super(ScreeningForm, self).__init__(*args, **kwargs)
        self.fields['blood_screen_type'] =  CommaSeparatedCharField(
            label=self.fields['blood_screen_type'].label,
            initial=self.fields['blood_screen_type'].initial,
            required=False,
            widget=CommaSeparatedSelectMultiple(choices=BLOOD_SCREEN_TYPE_CHOICES)
        )

class ScreeningAdmin(admin.ModelAdmin):
    #form = ScreeningForm
    form = ScreeningForm(initial={'log_user':get_current_user()})

Now I want to pass an initial value for a field of the Person class. How can I do that?

You can pass initial value to a ModelForm like this:

form = PersonForm(initial={'fieldname': value})

For example, if you wanted to set initial age to 24 and name to "John Doe":

form = PersonForm(initial={'age': 24, 'name': 'John Doe'})

Update

I think this addresses your actual question:

def my_form_factory(user_object):
    class PersonForm(forms.ModelForm):
        # however you define your form field, you can pass the initial here
        log_user = models.ChoiceField(choices=SOME_CHOICES, initial=user_object)
        ...
    return PersonForm

class PersonAdmin(admin.ModelAdmin):
    form = my_form_factory(get_current_user())

In case anyone is still wondering, the following works to set initial values for an Admin form:

class PersonAdmin(admin.ModelAdmin):
    def get_form(self, request, obj=None, **kwargs):
        form = super(PersonAdmin, self).get_form(request, obj=obj, **kwargs)
        form.base_fields['log_user'].initial = get_current_user()
        return form

Note that you can also set initial values via URL parameters: e.g. /admin/person/add?log_user=me

As your ModelForm is bound to the Person-Model, you could either pass a Person-Instance:

form = PersonForm(instance=Person.objects.get(foo=bar)

or overwrite the ModelForm's init-method:

class PersonForm(forms.ModelForm):

    def __init__(self, *args, **kwargs):
       super(PersonForm, self).__init__(*args, **kwargs)
       self.fields['foo'].value = 'bar'

    class Meta:
        model = Person
        exclude = ['name']

This is untested. I'm not sure whether "value" is correct, I'm not having a Django-Installation here, but basically this is the way it works.