next or previous item within an ordered, filtered queryset in Django

Question

How can I make transitions to the next article from the post_details(DetailView), so that both the next article and the previous one are available ?

vievs.py

class HomeView(ListView):
    model = Post
    #queryset = Post.objects.filter(status=1)
    cats = Category.objects.all()
    template_name = 'home.html'
    #ordering = ['-post_date']
    paginate_by = 6

    def get_context_data(self, *args, **kwargs):
        cat_menu = Category.objects.all()
        context = super(HomeView, self).get_context_data(*args, **kwargs)
        context["cat_menu"] = cat_menu
        return context


class ArticleDetailView(HitCountDetailView):
    model = Post
    template_name = 'post_detail.html'
    count_hit = True


    def get_context_data(self, *args, **kwargs):
        cat_menu = Category.objects.all()
        context = super(ArticleDetailView, self).get_context_data(*args, **kwargs)
        
        stuff = get_object_or_404(Post, id=self.kwargs['pk'])
        total_likes = stuff.total_likes()

        context["cat_menu"] = cat_menu
        context["total_likes"] = total_likes

        return context

Sort by date and ID

Answer 1

If you want the previous or next item based on a DateTimeField, you can work with .get_previous_by_fieldname(…) [Django-doc] or .get_next_by_fieldname(…) [Django-doc]. You thus can obtain the previous/next item for stuff with:

try:
    prev_stuff = stuff.get_previous_by_post_date()
except Stuff.DoesNotExist:
    prev_stuff = None

try:
    next_stuff = stuff.get_next_by_post_date()
except Stuff.DoesNotExist:
    next_stuff = None