Question

I have three models all associated with eachother via has_many :through method.

ProgramCategory
ProgramSubcategory
Program

Inside my application, I need to use ProgramCategory.title, ProgramSubcategory.title and Program.title very often. Lets say, there’ll be a dynamic sidebar menu and it will look like this:

|- Shows (ProgramCategory)
  |- Action (ProgramSubcategory)
    |- Lost (Program)
    |- Games of Thrones (Program)
    |- Dexter (Program)

Since I’m aware of power of application_controller, application_helper and partials; I feel lost about combining all of these together to find the most appropriate way.

Where and how should I call my models? Where should I build my methods to have access it through all of my controllers? Should I simply create a partial and render it at application layout?

I need some expert enlightment, please…

Thanks.

Answer 1

This navigation bar is not a core part of the data you are showing, it will be more or less the same for all pages. Thus, it does not belong to the controller.

Make it a helper method, and cache its results in the view:

app/helpers/sidebar_helper.rb

module SidebarHelper
  def sidebar_data
    # blahblah, use any tag helper (include it here if necessary)
    # just remember to 
  end
end

app/controllers/your_controller.rb

class YourController < ApplicationController
  helper :sidebar
  # ...

(or put the helper method in your application helper to have it available everywhere)

app/views/application/_sidebar.html.haml

- cache do
  # well, put here whatever you need to output the sidebar
  # use the sidebar_data, which should return precooked data on 
  # which you can build your nested <ul>s.
  # just indent it two spaces, so it's inside the "cache do" block

or app/views/application/_sidebar.html.erb

<% cache do %>
  same as above, don't worry about indentation
<% end -%>

and include the partial where appropriate

<%= render 'sidebar' %>