Multiple View urls to same template?

Using Django
1

I have this view info:

def tracker(request):
    object = Fcttracker.objects.all()[:1].get()
    object_id = object.rbid
    prev_id = Fcttracker.objects.all()[:1].get().rbid
     next_id = Fcttracker.objects.filter(rbid__exact=object_id+1).get().rbid

    context = {'data': object,
               'prev': prev_id,
               'next': next_id,
              }       

    return render(request, 'tracker.html', context)

def show_tracker(request, id):
    try:
        object = Fcttracker.objects.filter(rbid__exact=id)
    except Fcttracker.DoesNotExist:
        raise Http404("Record does not exist")         

    prev_id = id - 1
    next_id = id + 1
    context = {'data': object,
               'prev': prev_id,
               'next': next_id,
              }

    return render(request, 'tracker.html', context)

Tracker is called first because there is no id. If the next and previous are clicked it’s supposed to take the rbid and then call show_tracker with that id. But I get this error:

Reverse for 'tracker' with arguments '('',)' not found. 2 pattern(s) tried: ['redbud_site/tracker/(?P<id>[0-9]+)/$', 'redbud_site/tracker/$']

Is that because I originally called it with no arguments. I would have thought one way or the other it would have found one of those. My url pattern for this is:

urlpatterns = [
        path('', views.index, name='index'),       path('cma_unassigned/', views.cma_unassigned, name='cma_unassigned'),
        path('tracker/', views.tracker, name='tracker'),
        path('tracker/<int:id>/', views.show_tracker, name='tracker'),
    ]

I was hoping that would catch when to insert an id. I’m trying to have a next/previous buttons to move the record set forward thru the model or queryset. And thought I should call each record by it’s ID.

2

It looks like you’re trying to reverse the URL with a null string as an argument, but not without an argument.

As a quick test, you could try something like:
path('tracker/<str:something>/', views.tracker, name='tracker'),
to verify whether or not Django is going to interpret that as a null string and match this pattern.