Question

I have 2 models: Microposts (which has_many :comments) and Comments (which belongs_to :micropost).

In the following view:

views/micropost/index.html.erb:

<h2>Micropost Index</h2>
<% @microposts.each do |micropost| %>
  <h2><%= micropost.title %></h2>
  <p><%= micropost.content %></p>
  <p><%= micropost.comments.count %></p>
  <ul>
    <li><%= link_to 'Show', micropost %></li>
    <li><%= link_to 'Edit', edit_micropost_path(micropost) %></li>
    <li><%= link_to 'Destroy', micropost, confirm: 'Are you sure?', method: :delete %></li>
  </ul>
  <br />
<% end %>

controller/microposts.rb:

  def index
    @microposts = Micropost.all
  end

I was able to get the number of comments for each micropost:

<p><%= micropost.comments.count %></p>

How can I sort microposts by number of comments?

Any suggestions to accomplish this?

Answer 1

You can create a method in micropost.rb and sort by it like a virtual attribute:

def comments_count
  comments.count
end

Then sort your collection with sort_by method:

<% @microposts.sort_by(&:comments_count).map do |micropost| %>
  <%= micropost.title %>
  ...
<% end %>

Also, you can use reverse method if you need an opposite sort direction.