On Fri, Dec 4, 2009 at 6:04 AM, Andreas Kuntzagk < andreas.kuntz...@mdc-berlin.de> wrote:
> Hi, > > have a (probably simple) problem using ModelForms. I'm following this > guide: > http://docs.djangoproject.com/en/1.0/topics/forms/modelforms/ > > Here are my models: > > class Run(models.Model): > name = models.CharField(max_length=200) > > class RunForm(ModelForm): > class Meta: > model = Run > > > I already have some objects of class Run. But I don't know how to work > with them and the ModelForm > > >>> r = Run.objects.get(pk=1) > >>> f=RunForm(instance=r) > >>> f.is_valid() > False > >>> f.save() > Traceback (most recent call last): > File "<console>", line 1, in <module> > File "/usr/lib/python2.5/site-packages/django/forms/models.py", line > 407, in save > fail_message, commit, exclude=self._meta.exclude) > File "/usr/lib/python2.5/site-packages/django/forms/models.py", line > 43, in save_instance > cleaned_data = form.cleaned_data > AttributeError: 'RunForm' object has no attribute 'cleaned_data' > >>> f.errors > {} > >>> > > What did I misunderstood? > > I think the documentation that shows you can successfully call save() on a ModelForm created with just an instance parameter is incorrect. Providing the instance argument but no data dictionary on creation makes the form unbound. An unbound form has no data to validate or save. The save() code is tripping up because it is assuming it is dealing with a bound form, which would have the cleaned_data attribute. To actually update an instance based on submitted data, you would supply the POST data as the data dictionary when creating the form -- the code that is shown last in the green box: http://docs.djangoproject.com/en/dev/topics/forms/modelforms/#the-save-method Karen Karen -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-us...@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
