Inline formset for many to many relation

[Suraj]

Hello Everyone,

I want to inline formset for m2m relationship. Related code looks as follows:

models.py

```

class Outcome(models.Model):

    # some fields

   # Foreign key is created to make outcomes inline in course form

   course_outcome = models.ForeignKey("course.Course", on_delete=models.SET_NULL, blank=True, null=True)

class Course(models.Model):

   # some fields

   course_outcome = models.ManyToManyField(Outcome, verbose_name=COURSE_SINGULAR + " outcome", blank=True)

```

forms.py

```

class OutcomeForm(forms.ModelForm):

   # some fields

class CourseForm(forms.ModelForm):

   # some fields including inline outcomes

OutcomeFormSet = inlineformset_factory(parent_model=Course, model=Outcome, form=OutcomeForm, extra=1, can_delete=True)

```

views.py

```

class CourseCreateForm(CreateView):

   model = Course

   template_name = "course/course_form.html"

   form_class = CourseForm

   success_url = reverse_lazy("course")

   def get_context_data(self, **kwargs):

      context = super(CourseCreateForm, self).get_context_data(**kwargs)

      if self.request.POST:

         context["outcomes"] = OutcomeFormSet(self.request.POST)

      else:

         context["outcomes"] = OutcomeFormSet()

      return context

   def form_valid(self, form, **kwargs):

      super(CourseCreateForm, self).get_context_data(**kwargs)

      context = self.get_context_data()

      outcomes = context["outcomes"]

      with transaction.atomic():

         if outcomes.is_valid():

            self.object = form.save()

            outcomes.instance = self.object

            outcomes.save()

            form.instance.course_outcome.set(Outcome.objects.filter(course_outcome=self.object))

            form.save()

      return super().form_valid(form)

```

All my data in Outcome and Course models saved successfully except m2m field of course model.

Can anyone please guide me what I am doing wrong here.

Thanks in advance,

--
Suraj
https://hacksj4u.wordpress.com
https://github.com/SurajDadral