/**
  *
  * @param \GridField $gridField
  * @param \DataObject $record
  * @param string $columnName
  * @return string|null - the HTML for the column
  */
 public function getColumnContent($gridField, $record, $columnName)
 {
     if (!$record instanceof \Payment) {
         return null;
     }
     if (!$record->canVoid()) {
         return null;
     }
     \Requirements::css('omnipay-ui/css/omnipay-ui-cms.css');
     \Requirements::javascript('omnipay-ui/javascript/omnipay-ui-cms.js');
     \Requirements::add_i18n_javascript('omnipay-ui/javascript/lang');
     /** @var \GridField_FormAction $field */
     $field = \GridField_FormAction::create($gridField, 'VoidPayment' . $record->ID, false, 'voidpayment', array('RecordID' => $record->ID))->addExtraClass('gridfield-button-void payment-dialog-button')->setAttribute('title', _t('GridFieldVoidAction.Title', 'Void Payment'))->setAttribute('data-icon', 'button-void')->setAttribute('data-dialog', json_encode(array('maxAmount' => $record->dbObject('Money')->Nice(), 'hasAmountField' => false, 'infoTextKey' => 'VoidInfo', 'buttonTextKey' => 'VoidPayment')))->setDescription(_t('GridFieldVoidAction.Description', 'Void an authorized payment'));
     return $field->Field();
 }