Different types of Generic views

generic_views.txt

LIST VIEW:
    from django.views.generic import ListView

    ** Simple example
        class UsersListView(ListView):
            model = User
   
   ** You can add attributes to change the default behaviour.
        class UsersListView(ListView):
            model = User
            context_object_name = 'my_user_list'   # your own name for the list as a template variable
            queryset = User.objects.filter(title__icontains='war')[:5] # Get 5 books containing the title war
            template_name = 'users/my_arbitrary_template_name_list.html'  # Specify your own template name/location
   
   ** Overriding methods
        class UsersListView(ListView):
            model = User

            def get_queryset(self):
                return User.objects.filter(title__icontains='war')[:5] # Get 5 books containing the title war

   ** override get_context_data() in order to pass additional context variables to the template
        class UsersListView(ListView):
            model = User

            def get_context_data(self, **kwargs):
                # Call the base implementation first to get the context
                context = super(UsersListView, self).get_context_data(**kwargs)
                # Create any data and add it to the context
                context['some_data'] = 'This is just some data'
                return context
   
DETAIL VIEW:
        URL file: 
            urlpatterns = [
                path('book/<int:pk>', views.BookDetailView.as_view(), name='book-detail'),
            ]
        View File :
            from django.views.generic import DetailView
            
            ** simple example :
                class BookDetailView(DetailView):
                    model = Book

FORM VIEW:
        View File:
            from django.views.generic import FormView
            ** Simple example
                class ContactView(FormView):
                    form_class = ContactForm
                    template_name = 'contact-us.html'
                    success_url = reverse_lazy('<app-name>:contact-us')

                    def form_valid(self, form):
                        self.send_mail(form.cleaned_data)
                        return super(ContactView, self).form_valid(form)

            ** Add Additional data
                class ContactView(FormView):
                    form_class = ContactForm
                    template_name = 'contact-us.html'
                    success_url = reverse_lazy('<app_name>:contact-us')

                    def get_initial(self):
                        initial = super(ContactView, self).get_initial()
                        if self.request.user.is_authenticated:
                            initial.update({'name': self.request.user.get_full_name()})
                        return initial

                    def form_valid(self, form):
                        self.send_mail(form.cleaned_data)
                        return super(ContactView, self).form_valid(form)
                        
CREATE VIEW :
        View File:
            from django.views.generic import CreateView
            
            ** Simple Example
                class BookCreateView(CreateView):
                    template_name = 'books/book-create.html'
                    form_class = BookCreateForm

            ** Adding initial data to CreateView
            class BookCreateView(CreateView):
                template_name = 'books/book-create.html'
                form_class = BookCreateForm

                def get_initial(self, *args, **kwargs):
                    initial = super(BookCreateView, self).get_initial(**kwargs)
                    initial['title'] = 'My Title'
                    return initial

UPDATE VIEW:
        ** view file:
            class PostUpdateView(UpdateView):
            model = Post
            fields = ('message', )
            template_name = 'edit_post.html'
            pk_url_kwarg = 'post_pk'
            context_object_name = 'post'

            def form_valid(self, form):
                post = form.save(commit=False)
                post.updated_by = self.request.user
                post.updated_at = timezone.now()
                post.save()
                return redirect('topic_posts', pk=post.topic.board.pk, topic_pk=post.topic.pk)

        ** Note : With the UpdateView and the CreateView, we have the option to either define form_class or the fields attribute. In the example above we are using the fields attribute to create a model form on-the-fly. 


DELETE VIEW :
        ** view file :
            from django.views.generic import DeleteView
            from django.http import Http404

            class MyDeleteView(DeleteView):
                def get_object(self, queryset=None):
                    """ Hook to ensure object is owned by request.user. """
                    obj = super(MyDeleteView, self).get_object()
                    if not obj.owner == self.request.user:
                        raise Http404
                    return obj