openproject/app/views/cost_reports/_group_by.rhtml

<script type="text/javascript">
  //<![CDATA[
    function group_by_changed()
    {
      $('group_by[granularity]').setStyle({
        'display': <%= @query.time_groups.inject([]){|r,t| r<<t.to_s}.inspect %>.include($("group_by[name]").value) ? 'inline' : 'none'});
    }
  //]]>
</script>

<%=
  select_tag "group_by[name]", options_for_select(@query.group_by_columns_for_select, (@query.group_by[:name].to_s unless @query.group_by[:name].blank?)),
    :class => "select-small", :onchange => "group_by_changed();"
%>
<%=
  select_tag("group_by[granularity]", options_for_select([[l(:label_year), "year"], [l(:label_month), "month"], [l(:label_week), "week"], [l(:label_day_plural), "day"]], @query.group_by[:granularity]),
    :class => "select-small", :onload => "group_by_changed();", :style => ("display: none" if @query.group_by["name"].blank? || !@query.time_groups.include?(@query.group_by["name"].to_s))) 
%>