Adding a field to a form during runtime
Marek W
Here's my view code:
def __init__(self, *args, **kwargs):
super(CarForm, self).__init__(*args, **kwargs)
self.fields['extraField'] = forms.CharField()
class Meta:
model = Car
class CarPhotoForm(ModelForm):
class Meta:
model = CarPhoto
def car(request, template_name = 'cars.html'):
carForm = CarForm(True)
carPhotoForm = CarPhotoForm()
return render_to_response(template_name, {'carForm' : carForm, 'carPhotoForm' : carPhotoForm})
And here's a model:
car_type = models.CharField(max_length = 50)
class CarPhoto(models.Model):
photo = models.ImageField( upload_to = 'cars_photos/')
car = models.ForeignKey(Car)
The template is very simple too:
<h4>Car form:</h4>
<form id="carForm" method="POST" action=".">
{{carForm.as_p}}
<input type="Submit" value="Add car"/>
</form>
<h4>Car photo form:</h4>
<form id="carPhotoForm" method="POST" action=".">
{{carPhotoForm.as_p}}
<input type="Submit" value="Add photo"/>
</form>
I took this idea from http://www.b-list.org/weblog/2008/nov/09/dynamic-forms/. When I try to view the page, when there's my own __init__ method in CarForm class, then the car form doesn't contain any field. When i remove the __init__ method, everything works correctly. How to add a field to a form during a runtime ?
Thanks in advance,
Marek
Thomas Guettler
your code looks correct.
You can try to debug it. Maybe insert
assert False, self.fields into __init__()
Do the fields from the model exist?
Thomas
Marek W schrieb:
> Hi, I would like to add a field to a form dynamically. I'm using Django
> 1.0.2.
>
> Here's my view code:
>
> class CarForm(ModelForm):
> def __init__(self, *args, **kwargs):
> super(CarForm, self).__init__(*args, **kwargs)
> self.fields['extraField'] = forms.CharField()
>
> class Meta:
> model = Car
...
> I took this idea from
> http://www.b-list.org/weblog/2008/nov/09/dynamic-forms/. When I try to view
> the page, when there's my own __init__ method in CarForm class, then the car
> form doesn't contain any field. When i remove the __init__ method,
> everything works correctly. How to add a field to a form during a runtime ?
--
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de
Marek W
while to create a dynamic form this way:
def make_car_form(extra):
fields = { 'carType' : forms.CharField() }
if extra:
fields['extraField'] = forms.CharField()
return type('ContactForm', (forms.BaseForm, ), { 'base_fields': fields })
View method:
(...)
carForm = make_car_form(True)
(...)
then on the page there aren't any fields, whether calling make_car_form with extra=True or extra=False.
Regards,
Marek
--
Pozdrawiam,
Marek Wawrzyczek
Thomas Guettler
at runtime (*). I think using __init__() is better, and I guess
you can solve your problem with it, too.
(*) type('ContactForm', (forms.BaseForm, ), { 'base_fields': fields})
Marek W schrieb:
> Thanks for your response. Probably the reason was I didn't update a
> database, because now(after making syncdb) it works correctly. But by the
> time I've found a second problem:
>
> while to create a dynamic form this way:
>
> def make_car_form(extra):
> fields = { 'carType' : forms.CharField() }
> if extra:
> fields['extraField'] = forms.CharField()
> return type('ContactForm', (forms.BaseForm, ), { 'base_fields': fields
> })
>
>
> View method:
> (...)
> carForm = make_car_form(True)
> (...)
>
> then on the page there aren't any fields, whether calling make_car_form with
> extra=True or extra=False.
Preston Timmons
I think that your problem is that the make_car_form function returns a
form class rather than an instance of that class. Once you have the
class you still need to make an instance of it. Something like this
might work:
form_class = make_car_form(True)
carForm = form_class()
Preston