/**
  * HTML for the column, content of the <td> element.
  * 
  * @param GridField  $gridField  GridField to get column content for
  * @param DataObject $record     Record displayed in this row
  * @param string     $columnName Name of the column to get content for
  * 
  * @return string HTML for the column. Return NULL to skip.
  */
 public function getColumnContent($gridField, $record, $columnName)
 {
     if ($columnName == $this->columnName) {
         $quickAccessData = '';
         $quickAccessFields = $record->getQuickAccessFields();
         if ($quickAccessFields instanceof FieldList) {
             $quickAccessData = $quickAccessFields->renderWith('SilvercartGridFieldQuickAccessFields');
         } else {
             $quickAccessData = $quickAccessFields;
         }
         return '<span class="icon icon-24 icon-magnifier cursor-context-menu TriggerSilvercartQuickAccess">' . $quickAccessData . '</span>';
     }
 }