Can't add field to ModelForm at __init__

Question

I have a problem with ModelForm. Field test1 is displayed, but test2- is not. Playing with base_fields didn't help.

# models.py
class Country(models.Model):
    name = CharField(max_length=100)

# admin.py
class CountryAdminForm(ModelForm):
    test1 = forms.CharField('test1')

    def __init__(self, *args, **kwargs):
        super(CountryAdminForm, self).__init__(*args, **kwargs)
        self.fields['test2'] = forms.CharField('test2')

    class Meta:
        model = Country

class CountryAdmin(admin.ModelAdmin):
    form = CountryAdminForm

admin.site.register(Country, CountryAdmin)

Thank you.

Answer 1

Solved!

class CountryAdminForm(ModelForm):
    test1 = forms.CharField('test1')

    def __init__(self, *args, **kwargs):
        super(CountryAdminForm, self).__init__(*args, **kwargs)
        self.fields['test2'] = forms.CharField('test2')
        self.Meta.fields.append('test2')

    class Meta:
        model = Country
        fields = ['name', 'test1',]

...

Answer 2

I couldn't use self.Meta.fields.append in Django 1.4, because the fields in question is a tuple. You have to concatenate with self.Meta.fields += ('another_field',) instead, for example.