diff --git a/virtual_field.module b/virtual_field.module
index 24e7648..742b4be 100644
--- a/virtual_field.module
+++ b/virtual_field.module
@@ -97,7 +97,7 @@ function virtual_field_field_widget_info() {
   return array(
     'hidden' => array(
       'label' => t('Hidden (Automatic)'),
-      'field types' => array(),
+      'field types' => array_keys($fields),
     ),
   );
 }