/**
  * Return files by URL. Files will be ordered by filename
  *
  * @param ProjectFolder $folder
  * @param boolean $show_private
  * @return array
  */
 static function getByFolder(ProjectFolder $folder, $show_private = false)
 {
     $project = $folder->getProject();
     if (!$project instanceof Project) {
         return null;
     }
     // if
     if ($show_private) {
         $conditions = array('`project_id` =? AND `folder_id` = ?', $project->getId(), $folder->getId());
     } else {
         $conditions = array('`project_id` =? AND `folder_id` = ? AND `is_private` = ?', $project->getId(), $folder->getId(), false);
     }
     // if
     return self::findAll(array('conditions' => $conditions, 'order' => '`filename`'));
 }