Django Forms: pass parameter to form - django

Question

How do I pass a parameter to my form?
someView()..
form = StylesForm(data_dict) # I also want to pass in site_id here.
class StylesForm(forms.Form):
# I want access to site_id here

Answer 1

You should define the __init__ method of your form, like that:
class StylesForm(forms.Form):
def __init__(self,*args,**kwargs):
self.site_id = kwargs.pop('site_id')
super(StylesForm,self).__init__(*args,**kwargs)
of course you cannot access self.site_id until the object has been created, so the line:
height = forms.CharField(widget=forms.TextInput(attrs={'size':site_id}))
makes no sense. You have to add the attribute to the widget after the form has been created. Try something like this:
class StylesForm(forms.Form):
def __init__(self,*args,**kwargs):
self.site_id = kwargs.pop('site_id')
super(StylesForm,self).__init__(*args,**kwargs)
self.fields['height'].widget = forms.TextInput(attrs={'size':site_id})
height = forms.CharField()
(not tested)

Answer 2

This is what worked for me. I was trying to make a custom form . This field in the model is a charfield but I wanted a choice field generated dynamically .
The Form:
class AddRatingForRound(forms.ModelForm):
def __init__(self, round_list, *args, **kwargs):
super(AddRatingForRound, self).__init__(*args, **kwargs)
self.fields['name'] = forms.ChoiceField(choices=tuple([(name, name) for name in round_list]))
class Meta:
model = models.RatingSheet
fields = ('name', )
The Views:
interview = Interview.objects.get(pk=interview_pk)
all_rounds = interview.round_set.order_by('created_at')
all_round_names = [rnd.name for rnd in all_rounds]
form = forms.AddRatingForRound(all_round_names)
return render(request, 'add_rating.html', {'form': form, 'interview': interview, 'rounds': all_rounds})
The Template:
<form method="post">
{% csrf_token %}
{% if interview %}
{{ interview }}
{% if rounds %}
{{ form.as_p }}
<input type="submit" value="Submit" />
{% else %}
<h3>No rounds found</h3>
{% endif %}
</form>

Answer 3

someView()..
form = StylesForm( 1, request.POST)
in forms.py
class StylesForm(forms.Form):
#overwrite __init__
def __init__(self,site_id,*args,**kwargs):
# call standard __init__
super().__init__(*args,**kwargs)
#extend __init__
self.fields['height'] =forms.CharField(widget=forms.TextInput(
attrs= {'size':site_id}))
height = forms.CharField()
or
someView()..
form = StylesForm(site_id = 1)
in forms.py
class StylesForm(forms.Form):
#overwrite __init__
def __init__(self,site_id):
# call standard __init__
super().__init__()
#extend __init__
self.fields['height'] =forms.CharField(widget=forms.TextInput(
attrs= {'size':site_id}))
height = forms.CharField()