Accessing Attributes in a Many-to-Many

Posted by tshauck on Stack Overflow See other posts from Stack Overflow or by tshauck
Published on 2011-01-17T01:15:28Z Indexed on 2011/01/17 1:53 UTC
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Hi,

I have a rails app and I'd like to be able to do something like task.labels.first.label_name to get the label name of a task. However, I get an undefined method label_name. I did a t = Task.first; t.labels.first.label_name in the console, and that worked so I'm not sure what's going on. Here's the models then the locations of the error:

class Categorization < ActiveRecord::Base
 belongs_to :label
 belongs_to :task
end

class Label < ActiveRecord::Base
  attr_accessible :label_name

  has_many :categorizations
  has_many :tasks, :through => :categorizations
end

class Task < ActiveRecord::Base
  attr_accessible :task

  has_many :categorizations
  has_many :labels, :through => :categorizations
end

The error is in the index

<% for task in @tasks %>
<tr>
  <td><%= task.task %></td>
  <td><%= task.labels.first.label_name %></td>
  <td><%= link_to "Show", task %></td>
  <td><%= link_to "Edit", edit_task_path(task) %></td>
  <td><%= link_to "Destroy", task, :confirm => 'Are you sure?', :method => :delete %></td>
</tr>

<% end %>

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