Question

I am trying to have an element index view displaying the associated projectname ( field from db project) and the experimenttype ( field from db experiment ) from has_many_through and belongs to/has many associated models

model element.rb

class Element < ActiveRecord::Base

has_many :project_elements   
has_many :projects, :through => :project_elements

has_many :experiments

attr_accessible :project_ids, :experiment_ids

model project.rb

class Project < ActiveRecord::Base

has_many :project_elements
has_many :elements, :through => :project_elements  

attr_accessible :projectname, :element_ids

model project_element.rb

class ProjectElement < ActiveRecord::Base
belongs_to :project
belongs_to :element
attr_accessible :project_id, :element_id

model experiment.rb

class Experiment < ActiveRecord::Base

belongs_to :element

has_many :welldish_experiments
has_many :welldishs, :through => :welldish_experiments

attr_accessible :exptype, :element_id

elements_controller.rb

  def index
   @elements = Element.all
   respond_to do |format|
     format.html # index.html.erb
     format.json { render json: @elements }
     end

/elements/index.html.erb

 <% @elements.each do |element| %>
  <tr>

    <td><%= element.experiments %></td>
    <td><%= element.projects %></td>    

when i do this , it shows me the whole associated project objet…
same for experiments
and i can’t figure it out how to restrict the display to one single attribute ?

alternatively since the the datas’s been generated using formtastic:

element/_form.html.erb

       <%= semantic_form_for @element do |f| %>    
       <%= f.inputs do %>  
         <%= f.input :projects, :label => "projet associé", :required => true%>
         <%= f.input :experiments, :label => "type d'experience",
     :as => :radio,       :collection => Experiment.all, :required => true %>    
       <% end %>
       <%= f.actions :submit, :cancel %>
       <% end %>

i wonder if there is a quick way from there to generate the index view ( with some render ‘form’ options maybe? )
any help would be appreciated…

Answer 1

the answer was here ( collect method ):
http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html

  <% @elements.each do |element| %>
       <tr>          
       <td><%= element.projects.collect { |a| a.projectname }%></td>
       </tr>
  <% end %>