How can create a model form in django with a one-to-one relation with another model

Question

I want to create a model form with a one-to-one relation with another model. i.e Model1 has a one-to-one relation with Model2. I want my form to show all the fields from Model1 as well as Model2. Also what is the best way to show this in a view.

Answer 1

You don't need to create the single form for two models. Use two django forms and place them inside the single <form> tag:

class Model1Form(forms.ModelForm):
    class Meta:
        model = Model1

class Model2Form(forms.ModelForm):
    class Meta:
        model = Model2
        exclude = ('model1_one_to_one_field', )

def create_models(request):
    if request.method == 'POST':
        form1 = Model1Form(request.POST)
        form2 = Model2Form(request.POST)
        if all([form1.is_valid(), form2.is_valid()]):
            model1 = form1.save()
            model2 = form2.save(commit=False)
            model2.model1_one_to_one_field = model1
            model2.save()
            return redirect('create_models_success')
    else:
        form1 = Model1Form()
        form2 = Model2Form()
    return render(request, 'create_models.html',
                      {'form1': form1, 'form2': form2})

And then the create_models.html template:

<form action="." method="POST">
    {% csrf_token %}
    {{ form1.as_p }}
    {{ form2.as_p }}
    <button type="submit">Submit</button>
</form>