[Django] #21667: Allow dynamic form classes with WizardView
Django
-------------------------------+--------------------
Reporter: nickname123 | Owner: nobody
Type: New feature | Status: new
Component: Generic views | Version: 1.6
Severity: Normal | Keywords:
Triage Stage: Unreviewed | Has patch: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------+--------------------
The WizardView does not currently support dynamic form classes without
overriding the entire get_form method.
My mixin below demonstrates an easy way to make this convenient. I needed
this functionality to support using modelform_factory at runtime to
accommodate logic that varies depending on choices made previously in the
wizard. A simple use case is to support dynamic "required" fields.
{{{
class WizardDynamicFormClassMixin(object):
def get_form_class(self, step):
return self.form_list[step]
def get_form(self, step=None, data=None, files=None):
"""
This method was copied from the base Django 1.6 wizard class in
order to
support a callable `get_form_class` method which allows dynamic
modelforms.
Constructs the form for a given `step`. If no `step` is defined,
the
current step will be determined automatically.
The form will be initialized using the `data` argument to prefill
the
new form. If needed, instance or queryset (for `ModelForm` or
`ModelFormSet`) will be added too.
"""
if step is None:
step = self.steps.current
# prepare the kwargs for the form instance.
kwargs = self.get_form_kwargs(step)
kwargs.update({
'data': data,
'files': files,
'prefix': self.get_form_prefix(step, self.form_list[step]),
'initial': self.get_form_initial(step),
})
if issubclass(self.form_list[step], forms.ModelForm):
# If the form is based on ModelForm, add instance if available
# and not previously set.
kwargs.setdefault('instance', self.get_form_instance(step))
elif issubclass(self.form_list[step],
forms.models.BaseModelFormSet):
# If the form is based on ModelFormSet, add queryset if
available
# and not previous set.
kwargs.setdefault('queryset', self.get_form_instance(step))
return self.get_form_class(step)(**kwargs)
}}}
This is a simple demonstration of usage:
{{{
def get_form_class(self, step):
if step == STEP_FOO:
try:
choice_foo =
self.get_cleaned_data_for_step(STEP_FOO)["choice_foo"]
except KeyError:
pass
else:
# get_wizard_form_class() would return a model
form with fields
# that depend on the value of "choice"
return
ModelFoo(choice=choice_foo).get_wizard_form_class()
return super(WizardFoo, self).get_form_class(step)
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/21667>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
Django
Reporter: nickname123 | Owner: nobody
Type: New feature | Status: new
Severity: Normal | Resolution:
Keywords: | Triage Stage: Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
Changes (by aaugustin):
* needs_docs: => 0
* component: Generic views => contrib.formtools
* needs_tests: => 0
* needs_better_patch: => 0
--
Ticket URL: <https://code.djangoproject.com/ticket/21667#comment:1>
Django
Reporter: nickname123 | Owner: nobody
Type: New feature | Status: new
Severity: Normal | Resolution:
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by timo):
* stage: Unreviewed => Accepted
Comment:
Seems like it could be a useful hook.
--
Ticket URL: <https://code.djangoproject.com/ticket/21667#comment:2>
Django
Reporter: nickname123 | Owner: nobody
Type: New feature | Status: new
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by Fabio Caritas Barrionuevo da Luz <bnafta@…>):
* cc: bnafta@… (added)
--
Ticket URL: <https://code.djangoproject.com/ticket/21667#comment:3>
Django
Reporter: nickname123 | Owner: nobody
Type: New feature | Status: closed
Component: contrib.formtools | Version: 1.6
Severity: Normal | Resolution: fixed
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by gchp):
* status: new => closed
* resolution: => fixed
Comment:
formtools has been extracted into its own repository
(https://github.com/django/django-formtools/). Because of this, the issue
tracking for this package has been moved to GitHub issues. I'm going to
close this ticket, but I've created a GitHub issue to replace it where the
conversation can continue: https://github.com/django/django-
formtools/issues/16. Thanks!
--
Ticket URL: <https://code.djangoproject.com/ticket/21667#comment:4>