Creating UpdateForm by using ModelForm in Django

问题

I have a Django application and I wanna create an update form with ModelForm but I have to get the fields parameter from user_profile model. So I have created my form and view such as below.

forms.py;

class UpdateForm(forms.ModelForm):
    class Meta:
        model = Data
        fields = []
        
    def __init__(self, *args, **kwargs):
        input_choices = kwargs.pop('input_choices')
        super(UpdateForm, self).__init__(*args,**kwargs)
        self.fields = input_choices

views.py;

@login_required(login_url = "user:login")
def updateData(request,id):
    features = request.user.profile.selected_features
    instance = get_object_or_404(Data,id = id)
    
    form = UpdateForm(request.POST or None, input_choices=features, instance=instance)

    if form.is_valid():
        data = form.save(commit=False)
        data.author = request.user
        data.save()
        return redirect("data:dashboard")
    return render(request,"update.html",{"form":form})

However, I'm getting a list indices must be integers or slices, not str error in the return render(request,"update.html",{"form":form}) line. There is an issue with the fields parameter but I couldn't find anything.

How can I pass the fields parameter from view to ModelForm?

回答1:

You can use modelform_factory to create a form with dynamic fields

from django.forms import modelform_factory

@login_required(login_url = "user:login")
def updateData(request,id):
    features = request.user.profile.selected_features
    instance = get_object_or_404(Data, id=id)
    UpdateForm = modelform_factory(Data, fields=features)
    form = UpdateForm(request.POST or None, instance=instance)

If features is a queryset, you'll probably have to use something like features.values_list('name', flat=True) to get just the names of the fields

来源：https://stackoverflow.com/questions/62870567/creating-updateform-by-using-modelform-in-django