[FIXED] Django, how to set value in forms.ModelForm

Issue

I have a question for you. I have the following Model:

class Centro_di_costo(models.Model):
    centro_di_costo = models.CharField('Centro di costo', max_length=30)

    def __str__(self):
        return   self.centro_di_costo

class AltriCosti(models.Model):
    STATUS_CHOICES= [
        ('VARIABILE', 'VARIABILE'),
        ('FISSO', 'FISSO'),
    ]
    centro_di_costo = models.ForeignKey(Centro_di_costo) 
    sub_centro_di_costo = models.CharField('Categoria', max_length=30)
    status = models.CharField(choices=STATUS_CHOICES)
    price=models.DecimalField()
    quantity=models.IntegerField()

I use it in a lot of view, but in one of them I wanna set the value without passing from the POST request. So I have tried to set the ModelForm in the following manner:

class ModCollaboratori(forms.ModelForm):
    class Meta:
        model = AltriCosti
        fields = "__all__"

    def __init__(self, *args, **kwargs):
        super(ModCollaboratori, self).__init__(*args, **kwargs)
        self.helper = FormHelper()
        self.helper.form_show_labels = False
        self.fields['centro_di_costo'].value= "Servizi di Produzione"
        self.fields['sub_centro_di_costo'].value = "Collaboratori esterni"
        self.fields['status'].value = "VARIABILE"

But It does not work. How could I fix the code to work?

Solution

You can exclude fields from your form:

class ModCollaboratori(forms.ModelForm):
    class Meta:
        model = AltriCosti
        exclude = ['centro_di_costo', 'sub_centro_di_costo', 'status']

Then in your view you can "inject" value for these fields:

def some_view(request):
    if request.method == 'POST':
        form = ModCollaboratori(request.POST, request.FILES)
        if form.is_valid():
            form.instance.sub_centro_di_costo = 'Collaboratori esterni'
            form.instance.status = 'VARIABILE'
            form.instance.centro_di_costo = Centro_di_costo.objects.get_or_create(
                centro_di_costo='Servizi di Produzione'
            )[0]
            form.save()
            return redirect('name-of-some-view')
    else:
        form = ModCollaboratori()
    return render(request, 'some_template.html', {'form': form})

Answered By - Willem Van Onsem