public function onStorePropChange(iUmiEventPoint $e)
 {
     if ($e->getMode() != 'after') {
         return;
     }
     $propName = $e->getParam('property');
     $value = $e->getParam('newValue');
     $entity = $e->getRef('entity');
     if ($entity instanceof iUmiObject && $propName == 'primary' && $value == 1) {
         stores::clearPrimary($entity->getid());
     }
 }