_form.html.erb

<%= simple_form_for([@pacient, @retetum]) do |f| %>
  <%= f.error_notification %>

  <div class="inputs">
    <%= f.input :data %>
    <%= f.input :cantitate %>
    <%= f.input :serie %>
    <%= f.input :medicamente_id do %>
      <%#  select(:retetum, :medicamente_id, Medicamente.pastile) %>
      <%= select(:retetum, :medicamente_id, Medicamente.clase, 
      {:onchange => remote_function(:url => {:action => :update_pastile},
                                    :with => "'clasa='+value")} %>
    <% end %>
  </div>
  <div class="pastile"><%= render 'pastile', :collection => @retetum.pastile %></div>
  <br />
  <div class="actions">
    <%= f.button :submit %>
    <%= link_to 'Tipareste reteta', new_pacient_retetum_path(@pacient, :format=> 'pdf') %>
  </div>
<% end %>