gistfile1.txt

<%form_for(@main_group, :url=>main_group_path(@main_group), :html=>{:id=>"form_panel"}) do |form|%>
    <%=form.select(:group_ids, @groups.collect{|g| [g.code, g.id]}, {}, 
      {:size=>4, :multiple=>true, :id=>'source_baugruppe_ids'})%>
    <%=form.submit '>>', {:class=>'btn_shift_right'}%>
    <%=form.submit '<<', {:class=>'btn_shift_left'}%>
    <%=form.select(:group_ids, @main_group.groups.collect{|g| [g.code, g.id]}, {}, {:size=>4, :multiple=>true, :class=>'destination'})%>
  <%-end-%>