public function getLastMessageTimestampByUserIdList($userIdList) { $result = array(); $userId = OW::getUser()->getId(); $messageList = $this->messageDao->findLastMessageByConversationIdListAndUserIdList($userId, $userIdList); foreach ($messageList as $message) { if ($message['recipientId'] == $userId) { $opponentId = $message['senderId']; } if ($message['senderId'] == $userId) { $opponentId = $message['recipientId']; } if (isset($result[$opponentId])) { if ($result[$opponentId] < (int) $message['timeStamp']) { $result[$opponentId] = (int) $message['timeStamp']; } } else { $result[$opponentId] = (int) $message['timeStamp']; } } return $result; }