我不断收到此错误 NOT NULL constraint failed: lists_listcreate.user_id

Question

I am trying to make a site where users can make lists and then view those lists. How my site is set up is the user creates the list and gives it a name and then they move on to the next page where they can add items to their list. The login prosses works fine and you can go to the creat list page just fine. however, when you hit next on the create list page and try to go to the page where you go to the page where you add items to the list it gives you this error: IntegrityError at /your_lists/new_list/ NOT NULL constraint failed: lists_listcreate.user_id

Views:

from django.shortcuts import render
from .models import List, ListIcon, ListCreate
from django.views.generic import TemplateView, CreateView
from django.views.generic.edit import FormView
from django.contrib.auth.mixins import LoginRequiredMixin
from . import models
from .forms import AddListItemForm, CreatListForm
from django.http import HttpResponseRedirect

# Create your views here.

class CreateList(CreateView, LoginRequiredMixin):
    model = ListCreate
    form_class = CreatListForm
    template_name ="lists/list_form.html"
    success_url = '/add_item/'

class AddListItem(CreateView, LoginRequiredMixin):
    model = List
    form_class = AddListItemForm
    template_name = "lists/AddListItem.html"
    def index(requst):
        list = CreateList.objects.all()
        if request.method == "POST":
            if "add_one_more" in requst.POST:
                list.save()
                return redirect("/")
            if "done" in requst.POST:
                return redirect("/lists/your_lists/")

class ViewAllLists(TemplateView, LoginRequiredMixin):
    model = ListIcon
    template_name = 'lists/EveryList.html'
    def get_user_list_icons(self, **kwargs):
        if request.user.is_authenticated():
            lists_by_user = ListIcon.objects.filter(user=request.user)
        return render(lists_by_user)

Models:

    from django.db import models
from django.contrib.auth import get_user_model
# Create your models here.
User = get_user_model()

class List(models.Model):
    user = models.ForeignKey(User, related_name='lists_ListIcon_user', on_delete=models.CASCADE)
    list_item = models.CharField(max_length=300, blank=True)

#class AddListItem(models.Model):

class ListCreate(models.Model):
    user = models.ForeignKey(User, related_name='lists_ListIcon_users', on_delete=models.CASCADE)
    list_names = models.CharField(max_length=100, default='Enter list name here')

class ListIcon(models.Model):
    user = models.ForeignKey(User, related_name='users', on_delete=models.CASCADE)
    list_title = models.ForeignKey(ListCreate, related_name='list_name', on_delete=models.CASCADE)

enter code here

Answer 1

You are getting this error because you are not passing a user when creating a list instance overriding the form_valid method should fix like this.

class AddListItem(CreateView, LoginRequiredMixin):
model = List
form_class = AddListItemForm
template_name = "lists/AddListItem.html"
def index(requst):
    list = CreateList.objects.all()
    if request.method == "POST":
        if "add_one_more" in requst.POST:
            list.save()
            return redirect("/")
        if "done" in requst.POST:
            return redirect("/lists/your_lists/")
        # add this 
    

def form_valid(self, form):
    form.instance.user = self.request.user # if you want it to be the request.user
    return super().form_valid(form)