This post shows how to create sidebar by editing layout view. (application.html.erb)
Rails version: 4.2.5
Assuming that Bootstrap is installed.
Edit application controller
use before_action method to pass variables to application.html.erb
application_controller.rb
class ApplicationController < ActionController::Base protect_from_forgery with: :exception before_action :set_page def set_page @categories = Category.all end end
Edit layout
application.html.erb
<!DOCTYPE html>
<html>
<head>
...
</head>
<body>
<div class="container">
<ul class="nav nav-tabs">
...
</ul>
<div class="col-md-10">
<%= yield %>
</div>
<div class="col-md-2"> <!--sidebar from here-->
<h3>Categories</h3>
<%= link_to "New Category", new_category_path, class: 'btn btn-success' %>
<div class="row">
<br>
<% @categories.each do |category| %>
<div class="media">
<div class="media-body">
<h5 class="media-heading">
<%= link_to category.name, category %>
</h5>
</div>
</div>
<% end %>
</div>
</div> <!-- sidebar up to here-->
</div>
</body>
</html>