/**
  * {@inheritdoc}
  */
 public function setColumnTransformers(array $transformers = [])
 {
     $collection = new ColumnTransformerCollection();
     foreach ($transformers as $column => $transformer) {
         $collection->add($column, $transformer);
     }
     $this->dataset->setDefaultContextOption('column_transformers', $collection);
 }
 /**
  * Processes the row data
  *
  * @param array $row
  *
  * @return array
  */
 protected function transformRow($row, ColumnTransformerCollection $transformers)
 {
     foreach ($row as $field => $value) {
         if ($transformers->has($field)) {
             $row[$field] = $transformers->get($field)->transformValue($value);
         }
     }
     return $row;
 }