/**
  * Get the label callback.
  *
  * @param $config
  *
  * @return callable
  */
 protected function getLabelCallback($config)
 {
     $labelFormatter = SQLUtil::createLabelFormatter($this->getDatabase(), $config->getTable(), $config->getKeyColumn());
     return $labelFormatter->getCallback();
 }
 /**
  * Prepare the label callback.
  *
  * @param $config
  *
  * @return callable
  */
 protected function prepareLabelCallback($config)
 {
     $labelFormatter = SQLUtil::createLabelFormatter($this->getDatabase(), $config->getTable(), 'id');
     $labelFormatter->setFields(array('headline', 'id'));
     $labelFormatter->setFormat('%s (ID %s)');
     return $labelFormatter->getCallback();
 }
 /**
  * Prepare the label callback.
  *
  * @param $config
  *
  * @return callable
  */
 protected function prepareLabelCallback($config)
 {
     $labelFormatter = SQLUtil::createLabelFormatter($this->getDatabase(), $config->getTable(), 'year');
     $labelFormatter->setFormat('%s');
     return $labelFormatter->getCallback();
 }