Display alert after form submitted Django - django

Question

I would like to display an alert box after a form has been submitted.
The box would be hidden when a user first visits the page and will display "new category created" or "category already exists" upon submission.
I think I know would I can do this in the template but I'm not sure how to pass the variable into the template on the redirect.
Below is the view. Any thoughts how I can accomplish this?
I appreciate the feedback.
#login_required
#locationed
def manage_cat_subcat(request, location):
form = AddCategory()
if request.method == 'POST':
form = AddCategory(request.POST)
if form.is_valid():
submitted_cat_name = form.cleaned_data['category_name']
_, was_created = Category.objects.get_or_create(name=submitted_cat_name)
return HttpResponseRedirect(reverse('manage_cat_subcat', args=(location.slug,)))
return render(request, 'inventory/manage_cat_subcat.html', {'location': location, 'form': form})

Answer 1

You don't have to use any hidden data, just use this:
https://docs.djangoproject.com/en/dev/ref/contrib/messages/#using-messages-in-views-and-templates

Answer 2

It looks like you're talking about rendering a dialog based upon a user submitting certain information. If so, I strongly recommend using JQuery to pull the value of the category field once the field loses focus, then pass that category information right away via an AJAX call to a dedicated method in your views file. Depending on the response, you'll show the appropriate dialog. So it would be something like this in your views.py:
#render_json
def ajax_category_check(request){
if request.method == 'POST' and 'category_name' in request.POST:
#insert your code that checks new or existing categories
#if the category exists...
return {'exists': True}
return {'exists': False}
}
One advantage of AJAX is that it makes the user experience a lot smoother by removing the burden of having them deal with form submission/browser page refreshing.
On the other hand, if you're talking about simply showing an alert dialog before the form is even submitted, intercept the form submission and show the dialog using JQuery:
$('form').click(function(event){
$('#dialog').show();
/* after a delay or after dialog confirmation, etc... */
$('form').submit();
});