Django ManyToMany .add() doesn't add the elements to the created object-CodePudding

This is in my template:

 <form hx-post="{% url 'orders:create' %}">
    {% csrf_token %}
    {% for service in venue.services.all %}
            <input type="checkbox" name="services" value="{{ service.id }}"> {{ service.name }}<br>
    {% endfor %}
        <button
          hx-include="[name='id']"
          type="submit"
          >
          <input type="hidden" value="{{ venue.id }}" name="id">
          Submit
        </button>
  </form>

And this is the view:

class OrderCreateView(CreateView):
    model = Order
    form_class = OrderForm
    template_name = "orders/order_page.html"
    success_url = reverse_lazy("orders:success")

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["venues"] = Venue.objects.all()
        return context

    def form_valid(self, form):
        if self.request.htmx:
            # Get the IDs of the chosen services
            service_ids = self.request.POST.getlist('services')

            # Set the venue field of the form
            form.instance.venue = Venue.objects.get(id=self.request.POST.get("id"))

            # Save the form
            self.object = form.save()

            # Add the chosen services to the Order object
            for service_id in service_ids:
                service = Service.objects.get(id=service_id)
                self.object.chosen_services.add(service)

            return super().form_valid(form)

The problem is that the object is being created but only the line with form.instance.venue works, the part where the chosen_services are being added doesn't work, the object is created without any of them. The service_ids variable is populated with the information from the front end, it has the ids that i need, it just doesn't add them to the object.

This is models.py:

class Order(models.Model):
   venue = models.ForeignKey(Venue, on_delete=models.SET_NULL, null=True)
   chosen_services = models.ManyToManyField(Service, null=True, blank=True)

CodePudding user response：

Try this code

Here m2m field is already handled by form, you need to just set the value of the venue field with save() method of form

def form_valid(self, form):
    if self.request.htmx:
        # Get the IDs of the chosen services
        service_ids = self.request.POST.getlist('services')
        fm = form.save()
        # Set the venue field of the form
        fm.venue = Venue.objects.get(id=self.request.POST.get("id"))
        fm.save()
        
        return super().form_valid(form)

CodePudding user response：

The problem was that in forms.py i had this:

class OrderForm(forms.ModelForm):
    class Meta:
        model = Order
        fields = ["chosen_services"]

I deleted that and now it works!