gistfile1.txt

<%= form_for(@technique) do |f| %>
  <% if @technique.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@technique.errors.count, "error") %> prohibited this technique from being saved:</h2>

      <ul>
      <% @technique.errors.full_messages.each do |msg| %>
        <li><%= msg %></li>
      <% end %>
      </ul>
    </div>
  <% end %>

  <div class="field">
    <%= f.label :name %><br>
    <%= f.text_field :name %>
  </div>
  <div class="field">
    <%= f.label :description %><br>
    <%= f.text_area :description,  size: "84x20" %>
  </div>

  <div class="field">
    <%= f.label :martialarts %><br>
    <%= select_tag 'technique[martialart_ids][]', options_from_collection_for_select(Martialart.all.order(:name), "id", "name", @technique.martialarts.map(&:id)), { :multiple => true, :size =>10 } %>
  </div>
  
  <div class="actions">
    <%= f.submit "Salvar" %>
  </div>
<% end %>