How to render an array in Rails

Question

In my Rails application, I have a class Bar and a controller FooController.

class Bar
   attr_accessor :id
end

class FooController < ApplicationController
   def index
      @rows = {}
      bar = Bar.new
      bar.id = 1
      @rows[0] = bar

      render "index"
   end
end

In the view, I would like to render like this

<table>
<% @rows.each do |bar| %>
  <tr>
    <td><%= bar.id %></td>
  </tr>
<% end %>  
</table>

But it will throws error

undefined method `id' for [0, #<Bar:0x00007fc65db33320 @id=1>]:Array

If I render like this:

<%= @rows %>

the raw data of the array @rows will be rendered as:

{0=>#<Bar:0x00007fc65db33320 @id="1">}

How do I render the elements one by one?

Answer 1

The problem is that @rows = {} doesn't assign an array but a hash. And therefore @rows[0] = bar doesn't store bar as the first element in the array, but it stores bar under the key in the hash.

Just change your controller method to:

def index
  @rows = []

  bar = Bar.new
  bar.id = 1

  @rows << bar

  render "index"
end