There are a few different ways to approach this depending on how your site is structured etc., and how fine gained you need it to be.
You could create a directory under templates named left_nav or sidebar etc., and create the matching view. Then place multiple templates in the templates/<your_name> directory for all of the different routes you have. Name each template the same as the route, e.g. settings.html.eex, and then render them into the parent template like this:
...
<%= render Myweb.SidebarView, "#{@route_name}.html", conn: @conn, ... %>
...
Where route_name is assigned to conn in the controller, or put into conn.private by a plug etc etc…
That’s just one quick idea, but like I said, it really depends more on your specific use case as to what would be the best solution.
