CODEWITHSUNDEEP
pythondjangodjango-forms
thornomad
thornomad

Reputation: 6797

Django: form values not updating when model updates

I am creating a form that uses MultipleChoiceField. The values for this field are derived from another model. This method works fine, however, I am noticing (on the production server) that when I add a new item to the model in question (NoticeType), the form does not dynamically update. I have to restart the server for the new item to show up on my MultipleChoiceField.

Any changes to the NoticeType model (editing items or creating new ones) do not propagate to the form. After I restart the production server, the updates appear.

Any ideas why this might be ? The relevant portion of the form is below. Thanks.

from django import forms 
from django.contrib.auth.models import User
from notification.models import NoticeType

class EditUserProfileForm(forms.Form):   
    CHOICES = []

    for notice in NoticeType.objects.all():
        CHOICES.append( (notice.label,notice.display) )

    notifications   = forms.MultipleChoiceField(
                        label="Email Notifications",
                        required=False,
                        choices=( CHOICES ),
                        widget=forms.CheckboxSelectMultiple,)

Upvotes: 6

Views: 2944

Answers (2)

Daniel Roseman
Daniel Roseman

Reputation: 600059

Although mherren is right that you can fix this problem by defining your choices in the __init__ method, there is an easier way: use the ModelMultipleChoiceField which is specifically designed to take a queryset, and updates dynamically.

class EditUserProfileForm(forms.Form):
    notifications = forms. ModelMultipleChoiceField(
                    label="Email Notifications",
                    required=False,
                    queryset = NoticeType.objects.all(),
                    widget=forms.CheckboxSelectMultiple)

Upvotes: 9

Billy Herren
Billy Herren

Reputation: 669

My hunch is that the class definition is only being processed once on load rather than for each instantiation. Try adding the CHOICES computation to the init method like so:

def __init__(self, *args, **kwargs):
    super(self.__class__, self).__init__(*args, **kwargs)
    CHOICES = []
    for notice in NoticeType.objects.all():
        CHOICES.append( (notice.label, notice.display) )
    self.fields['notifications'].choices = CHOICES

Upvotes: 7

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