Django -- Removing an option from queryset form field if already selected - django

Question

I have a form field that calls a queryset and uses the 'select' widget.
Is there a way to remove an option value from the queryset if it already has been 'added' to the cart?
In the select form, there's three options: Option A, Option B, Option C.
The user selects Option A, and clicks 'Add'. Now once the user clicks 'Add', I want to remove Option A from the select.
Only Option B and Option C will be available to choose from.
Can this be done just using Django+Python? Or will I need to use additional JS/jQuery?
Thanks!
models.py
class Pickup(models.Model):
# id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
user = models.ForeignKey(settings.AUTH_USER_MODEL, blank=False, null=True)
total = models.DecimalField(max_digits=100, decimal_places=2, default=0.00)
timestamp = models.DateTimeField(auto_now_add=True, auto_now=False)
updated = models.DateTimeField(auto_now_add=False, auto_now=True)
active = models.BooleanField(default=True)
status = models.CharField(max_length=120, choices=STATUS_CHOICES, default="Open")
def __str__(self):
return "Pickup Order ID: %s" %(str(self.id))
class PickupItem(models.Model):
pickup = models.ForeignKey('Pickup', null=True, blank=True)
dropoffitem = models.ForeignKey(DropoffItem)
notes = models.TextField(null=True, blank=True)
timestamp = models.DateTimeField(auto_now_add=True, auto_now=False)
updated = models.DateTimeField(auto_now_add=False, auto_now=True)
forms.py
class AddPickupItemForm(forms.ModelForm):
dropoffitem = forms.ModelChoiceField(queryset=DropoffItem.objects.all(), widget=forms.Select(attrs={'class':'form-control'}))
class Meta:
model = PickupItem
fields = ['dropoffitem']
views.py
def add_item_to_pickup_order(request):
request.session.set_expiry(120000)
try:
user = request.user
the_id = request.session['pickup_id']
pickup = Pickup.objects.get(id=the_id)
except:
user = request.user
new_pickup_order = Pickup(user=user)
new_pickup_order.save()
request.session['pickup_id'] = new_pickup_order.id
the_id = new_pickup_order.id
pickup = Pickup.objects.get(id=the_id)
try:
dropoffitem = DropoffItem.objects.get(id=id)
except DropoffItem.DoesNotExist:
pass
except:
pass
form = AddPickupItemForm(request.POST or None)
if request.method == "POST":
dropoffitem_id = int(request.POST['dropoffitem'])
pickup_item = PickupItem.objects.create(pickup=pickup, dropoffitem_id=dropoffitem_id)
pickup_item.save()
return HttpResponseRedirect('%s'%(reverse('add_item_to_pickup_order')))
context = {
"pickup": pickup,
"form": form,
}
return render(request, 'pickups/create_pickup_order.html', context)
.html
{% extends "base.html" %}
{% block content %}
<div class="row">
<div class="container">
<div class="col-xs-12">
<h1>Create Cart</h1>
<form method="POST" action="{% url 'add_item_to_pickup_order' %}">
{% csrf_token %}
<table class="table">
<thead>
<th>Item</th>
<th></th>
</thead>
<tr>
<td>{{ form.dropoffitem }}</td>
<td><input type="submit" value="Add Item" class="btn btn-default btn-primary" /></td>
</tr>
</table>
</form>

Answer 1

To exclude/remove an item from the queryset, you can use exclude.
YourModel.objects.exclude(id=4)
To exclude multiple items:
YourModel.objects.exclude(id__in=[4, 6, 10])
More info about exclude on Django docs.