How can I paginate this view?-CodePudding

I am trying to convert this function-based view to a class-based view for the purpose of pagination.

def tag(request, tag):    
    posts = Post.objects.filter(approved=True, tags__name__in=[tag]).order_by('-date_posted')
    return render(request, 'blog/tag.html', {'tag': tag, 'posts': posts})

I wrote it like this:

class TagView(ListView):
    model = Post
    template_name = 'blog/tag.html'
    context_object_name = 'posts'
    ordering = ['-date_posted']
    paginate_by = 3

    def get_queryset(self):
        return Post.objects.filter(approved=True, tags__name__in=[tag]).order_by('-date_posted')

But this does not display any posts when I load the page. Can anyone tell me why this is? Or if you know another way of paginating this view without converting it to a class-based view that would also be appreciated. Thank you in advance.

CodePudding user response：

In your ListView you are not passing any data into the [tag] variable, so your queryset is returning empty. Depending on what you're passing to it, you may or may not need the [] square brackets around it in the query.

If you are using a single string tag, eg, via the URL /tag/myTag then to pass data from the URL into a listview you can update your get_queryset method:

 def get_queryset(self):
        return Post.objects.filter(approved=True, tags__name__in=[self.kwargs['tag']]).order_by('-date_posted')

If you are passing an actual a list of tags, you may need to set it in a session variable in the previous view and recall it here

In the previous view

request.session['tags'] = list_of_tags

And in this view

tags = request.session['tags']
return Post.objects.filter(approved=True, tags__name__in=tags).order_by('-date_posted')