I have a model form that contains among other things a dropdown list of pupils (ModelMultipleChoiceField), which is initially empty but when a user selects a teacher, I get the list of pupils registered for this teacher via ajax request.
self.fields['pupil'] = forms.ModelMultipleChoiceField(queryset=Pupil.objects.none(),)
Everything works till the validation. Since initially queryset points to none, when a form is submitted it is returned with an error "It is invalid choice".
I can pass the entire set of pupils to the pupil field and then make it empty via jQuery but that looks ugly. What is the right way of doing it?
You can do it as follows. In this case first we render the form with empty queryset after you loading the choices with ajax. you will submit data with a post request. when we receive the POST request we are sending full queryset to the form.
In above case you explained the queryset is empty so you have got validation error as invalid choice. But, in this case we have full queryset so, it will work perfectly.
views.py
def sample_view(request):
if request.method == 'POST':
queryset = Pupil.objects.all()
form = SampleForm(request.POST, queryset=queryset)
# your code goes here
else:
queryset = Pupil.objects.none()
form = SampleForm(queryset=queryset)
# your code goes here
forms.py
class SampleForm(forms.ModelForm):
def __init__(self, *args, *kwargs):
queryset = kwargs.pop('queryset', None)
super(SampleForm, self).__init__(*args, **kwargs)
self.fields['pupil'] = forms.ModelMultipleChoiceField(queryset=queryset)
# your code
Related
I want to display initial values as selected on a MultipleChoice form field in Django when the form loads. I populate a formset with different forms. Each form has only one field 'answer', which is initialized based on a custom parameter passed to the form's init() method.
class AnswerForm(forms.Form):
def __init__(self, *args, **kwargs):
"""
Initialize label & field
:returns None:
"""
question = kwargs.pop('question') # A Question object
super(AnswerForm, self).__init__(*args, **kwargs)
if question.type == Types.RADIO:
choices_ = [(op.id, op) for op in question.option_set.all()]
self.fields['answer'] = forms.ChoiceField(label=question.statement,
initial=1,
widget=forms.RadioSelect,
choices=choices_)
elif question.type == Types.CHECKBOX:
choices_ = [(op.id, op) for op in question.option_set.all()]
self.fields['answer'] = forms.MultipleChoiceField(label=question.statement,
initial=[1,3],
widget=forms.CheckboxSelectMultiple,
choices=choices_)
This renders the following HTML:
But it doesn't get into the form's cleaned_data. When I submit formset, the request.POST data goes into this view:
def post(self, request, form_id):
"""
Process & save the responses obtained from a form into DB
:param request: An HTTPRequest object
:param form_id: form id whose responses arrive
:returns HttpResponse object with a results template
"""
formset = FormHandler.AnswerFormSet(request.POST, request.FILES,
form_kwargs={'questions': FormHandler.qs})
if formset.is_valid():
for form in formset:
cd = form.cleaned_data
# Access cd['answer'] here but cd appears to be empty dict {}
# with no key named 'answer'
The cleaned_data does have the correct 'answer' value in the case of Radio, but in this case, it doesn't contain the list of selected IDs which it should. I've checked that request.POST.getlist('form_#_answer') does show the correct list of ['1', '3'] but it somehow doesn't get into the formset's cleaned_data. I've spent hours trying to find out why this happens. Can't find the answer anywhere in the Django docs either. Can anyone explain why this is happening?
I'm new to python and trying to understand how to get a dynamic ModelChoiceField to work. It works fine when I select an object with all but I'm trying to get the dropdown to reflect a user's attribute. Here is my code:
Forms.py
class ViewByMake(forms.Form):
dropdown = forms.ModelChoiceField(queryset=Make.objects.none())
def __init__(self, user, *args, **kwargs):
user = kwargs.pop('user')
super(ViewByMake, self).__init__(*args, **kwargs)
qs = Make.objects.filter(user=user)
self.fields['dropdown'].queryset = qs
self.fields['dropdown'].widget.attrs['class'] = 'choices1'
self.fields['dropdown'].empty_label = ''
Views.py
def view_bymake(request):
form = ViewByMake(request.POST or None, user=request.user)
if request.method == 'POST':
if form.is_valid():
make = form.cleaned_data['dropdown']
return HttpResponseRedirect(make.get_absolute_url1())
return render(request,'make/view_make.html',{'form':form})
This code works fine if I remove all user= references but then only returns the full make objects list which is not what I want. I found a very similar question on StackOverflow, but when I duplicated the code identically, it still doesn't work and it is giving me the following error:
init() got multiple values for argument 'user'
I searched the end of the internet on this topic. I'm open to other ideas if I'm approaching this poorly. I'm trying to basically get a filtered list based on criteria associated with a user's profile. I definitely need the drop down field to be specific to a user based on a profile setting. Thanks for your help in advance. I'm running django 1.11.2 and Python 3.6.1.
This is the updated model which need to include the user attribute which I didn't realize that I had to specify:
class Make(models.Model):
name = models.CharField(max_length=264,unique=True)
user = models.ForeignKey(User,null=True,on_delete=models.CASCADE)
Try with request, send request from form and get request in init method of form
views.py
def view_bymake(request):
form = ViewByMake(request.POST or None, request=request)
forms.py
def __init__(self, user, *args, **kwargs):
self.request = kwargs.pop('request', None)
super(ViewByMake, self).__init__(*args, **kwargs)
qs = Make.objects.filter(user=self.request.user)
self.fields['dropdown'].queryset = qs
self.fields['dropdown'].widget.attrs['class'] = 'choices1'
self.fields['dropdown'].empty_label = ''
The answer to my original question, how do I get user=user to work consists of making sure that your form, view, and model all reference user. I originally had the user reference in the view and the form correct, but I neglected to make sure user= was specified on the model I was referencing. I thought it was built in, but turns out you have to specifically reference it on your model. I'm new at this so it was a learning experience. On to the next challenge!
I've created a form which is a forms.ModelForm. On the "view" side, I've created a view which is a generic.UpdateView.
In those 2 differents classes, I have is_valid() on one side, and form_valid() on the other side.
class ProfileForm(FormForceLocalizedDateFields):
class Meta:
model = Personne
fields = ('sexe', 'statut', 'est_fumeur',
'est_physique', 'date_naissance')
exclude = ('user', 'est_physique')
# blabla fields declaration
def is_valid(self):
pass
and edit view:
class EditView(LoginRequiredMixin, generic.UpdateView):
model = Personne
template_name = 'my_home/profile/edit.html'
form_class = ProfileForm
success_url = reverse_lazy('my_home_index')
# blabla get_initial() and get_object() and get_context_data()
def form_valid(self, form):
# username = form.cleaned_data['username']
# Hack: redirect on same URL:
# - if user refreshes, no form re-send
# - if user goes back, no form re-send too, classical refresh
site_web = u"{0}://{1}".format(
self.request.scheme, self.request.META['HTTP_HOST']
)
return HttpResponseRedirect(u'{0}{1}'.format(
site_web, self.request.META['PATH_INFO']
))
My form shows 3 fields of 3 different models :
User,
Person which has a foreign key to User
Picture which has a foreign key to Person
Where should I create the code that update those fields, and why?
generic.UpdateView is supposed to help us when updating fields, but it seems that when you have fields not belonging to the model you edit, you have to write all the "update" by hand.
is_valid on the surface just tells you whether or not the form is valid, and thats the only job it should ever do..
From the source code:
def is_valid(self):
"""
Returns True if the form has no errors. Otherwise, False. If errors are
being ignored, returns False.
"""
return self.is_bound and not self.errors
Underneath this, what it also does is (from docs)
run validation and return a boolean designating whether the data was valid:
The validation is ran because errors is a property that will call full_clean if the validation hasn't been called yet.
#property
def errors(self):
"Returns an ErrorDict for the data provided for the form"
if self._errors is None:
self.full_clean()
return self._errors
Where should I create the code that update those fields, and why?
In the form_valid method because by this point you've found out that your validation has verified that it is safe to update your model.
My django form has errors in the initial page load, before the form even has a chance to be submitted.
My view:
def example_function(request):
if request.method == 'POST':
# the request is GET
else:
form = MyForm(user=request.user)
import pdb;pdb.set_trace()
return render_to_response('templates/example.html', locals(), context_instance=RequestContext(request),)
Where I have my pdb imported, in the console I can see that my form already has errors. The output of form.errors in my console is all the fields in the model which are set to not null.
(Pdb) form.errors
{'example_field_1': [u'This field is required.'], 'example_field_2': [u'This field is required.']}
The form has not submit yet, but I am still getting errors. Can someone explain?
I'm using django 1.4.
My form:
class MyForm(forms.ModelForm):
captcha = ReCaptchaField()
_readonly_template = form.TextInput(attrs={'readonly':'readonly'})
first_name = forms.CharField(widget = _readonly_tempalte)
def __init__(self, data=None, *args, **kwargs):
data = data or {}
if 'user' in kwargs:
user = kwargs['user']
del kwargs['user']
data.update({
'first_name' : user.first_name,
})
super(MyForm, self).__init__(data, *args, **kwargs)
class Meta:
model = MyModel
My model:
class MyModel(models.Model):
first_name = models.CharField(max_length=255)
example_field_1 = models.CharField(max_length=255)
example_field_2 = models.CharField(max_length=255)
https://docs.djangoproject.com/en/1.8/ref/forms/validation/
accessing the form.errors attribute will trigger the various form validation methods. Those errors shouldn't show up when you render the form.
I'm not sure how the user field is structured, but keep in mind that if you want the user name, you may want to change that from request.user to request.user.username.
I hope you resolved your issue, but in case you haven't, I had a similar issue which I was able to resolve by using "or None" when setting the form after checking if it is a POST (or GET) request.
In your case it looks like this may be a slightly different issue, but I wondered if this snippet might fix things up:
if request.method == "POST":
form = MyForm(request.POST or None)
# .. do stuff....
else: #.....this is a GET
data = {'user': request.user.username} #note this is changed to username
form = MyForm(data)
Not sure if still useful, but adding it here, as I just ran into this for my ChoiceField items within my form.
I was getting the same error messages, but eventually found out I had forgotten to ad 'or None' when initiating the form inside my view.
The initial code inside my view function that was displaying the error messages from the start:
form=FormName(request.POST)
I just added the 'or None' to it:
form=FormName(request.POST or None)
And all good after that.
Don't you need to do something like this
form = NameForm(request.POST)
Rather then attempting to use the user object to populate the form? Will the user object have an example_field_1 in it?
https://docs.djangoproject.com/en/1.8/topics/forms/
This is the normal behavior.
Some properties of fields are checked on client side. The error messages belong to the form, are part of the html but are not displayed until needed. It saves a client-server request.
I have made a form to filter ListView
class SingleNewsView(ListView):
model = News
form_class = SearchForm
template_name = "single_news.html"
def get(self, request, pk, **kwargs):
self.pk = pk
pub_from = request.GET['pub_date_from']
pub_to = request.GET['pub_date_to']
return super(SingleNewsView,self).get(request,pk, **kwargs)
My form fields are pub_date_from and pub_date_to. When I run the site it says:
MultiValueDictKeyError .
I don't know what's going on. When I remove the two line of getting pub_from and pub_to the site works fine. I want these two values to filter the queryset.
On first request there is no form data submitted so request.GET would not have any data. So doing request.GET['pub_date_from'] will fail. You shall use .get() method
pub_from = request.GET.get('pub_date_from')
pub_to = request.GET.get('pub_date_to')
If these keys are not in the dict, will return None. So handle the such cases appropriately in your code.
Also, if you want to filter objects for ListView add get_queryset() method to return filtered queryset as explained here Dynamic filtering