how to change form variable values from view

i've been trying to send data to the following form from my view.

i need the variable (choices ) to change each time we call this form

class AnswersForm(forms.Form):

question  = forms.RadioSelect
CHOICES=[('sf','asdf')]
radioButton = forms.ChoiceField(choices=CHOICES, widget=forms.R开发者_运维知识库adioSelect())

view.py :

def exam_attend(request,ExamName,questionNo=0):

if ExamName:
    myList = [('b','a')]       
    forms.AnswersForm.CHOICES=myList
    form = forms.AnswersForm()

  variabls = RequestContext(request,{'form':form})
  return render_to_response('exam_pageAttend.html',variabls)

the problem is : i need the variable (CHOICES) from the form class to change it's value in the view class ( i know i can just use CHOICES = [('b','a')] ) but i want to change it from the view since this code is only to show the problem )

any better ideas ?

thanks in advance

You can change the field choices overriding the form init method (so that it accepts a choice parameter) or you can change the field's choices after the init, depending on your needs.

First Case would be like this:

class AnswersForm(forms.Form):
    radioButton = forms.ChoiceField(choices=CHOICES, widget=forms.RadioSelect())

    def __init__(self, radio_choices= None, *args, **kwargs):
        super(AnswersForm, self).__init__(self, *args, **kwargs)
        if radio_choices is not None:
            self.fields['radioButton'].choices = radio_choices

View example:

form_instance = AnswersForm(new_choices)