function onDisplayFilter(&$filter, $value = '', $formName = 'adminForm')
 {
     if (!in_array($filter->field_type, self::$field_types)) {
         return;
     }
     // ** some parameter shortcuts
     $label_filter = $filter->parameters->get('display_label_filter', 0);
     if ($label_filter == 2) {
         $text_select = $filter->label;
     } else {
         $text_select = JText::_('FLEXI_ALL');
     }
     $filter->html = '';
     if (!$filter->parameters->get('range', 0)) {
         // *** Retrieve values
         // *** Limit values, show only allowed values according to category configuration parameter 'limit_filter_values'
         $force = JRequest::getVar('view') == 'search' ? 'all' : 'default';
         $results = flexicontent_cats::getFilterValues($filter, $force);
         // *** Create the select form field used for filtering
         $options = array();
         $options[] = JHTML::_('select.option', '', '-' . $text_select . '-');
         foreach ($results as $result) {
             if (!strlen($result->value)) {
                 continue;
             }
             $options[] = JHTML::_('select.option', $result->value, JText::_($result->text));
         }
         if ($label_filter == 1) {
             $filter->html .= $filter->label . ': ';
         }
         $filter->html .= JHTML::_('select.genericlist', $options, 'filter_' . $filter->id, ' class="fc_field_filter" onchange="document.getElementById(\'' . $formName . '\').submit();"', 'value', 'text', $value);
     } else {
         //print_r($value);
         $size = (int) ($filter->parameters->get('size', 30) / 2);
         $filter->html .= '<input name="filter_' . $filter->id . '[1]" class="fc_field_filter" type="text" size="' . $size . '" value="' . @$value[1] . '" /> - ';
         $filter->html .= '<input name="filter_' . $filter->id . '[2]" class="fc_field_filter" type="text" size="' . $size . '" value="' . @$value[2] . '" />' . "\n";
     }
 }