/**
  * 添加或取消关注
  */
 public function toggleCollect($userId)
 {
     $owner = $this->getOwner();
     $collect = Collect::model()->findByAttributes(array('userId' => $userId, 'collectableEntityId' => $owner->entityId));
     if ($collect) {
         $collect->delete();
         return false;
     } else {
         $collect = new collect();
         $collect->userId = $userId;
         $collect->collectableEntityId = $owner->entityId;
         $collect->addTime = time();
         $collect->save();
         return true;
     }
 }