订购消防站文件

Question

我在firestore中进行了一次聊天，显然我需要从每个聊天室获取消息，但是消息永远不会按照日期和用户ID进行排序。

一开始我没有使用@ServerTimestamp，而是在Android设备本身上生成日期，但是根据Stackoverflow的建议，我改用了Firestore来生成日期，根据可以解决的建议，但是不起作用。它以我未订购的顺序排列，以用户ID lateinit var from_id: String

的顺序排列

class Message {

    lateinit var content: String

    @ServerTimestamp
    var timestamp: Timestamp ?= null

    lateinit var from_id: String

    lateinit var type: String

    constructor(content: String, timestamp : Timestamp, from_id: String, type: String) {
        this.content = content
        this.from_id = from_id
        this.timestamp = timestamp
        this.type = type
    }

    constructor(content: String, from_id: String, type: String) {
        this.content = content
        this.from_id = from_id
        this.type = type
    }

    constructor()
}

ControllerChat

...

   override fun sendMessageText(idChatRoom: String, from_id: String, text: String, listenerSendMessage: ListenerSendChatMessage) {
        var message = Message(text, from_id, Message.TEXT)

        chatChannelsCollectionRef
                .document(idChatRoom)
                .collection(MESSAGES)
                .add(message).addOnSuccessListener {
                    listenerSendMessage.onSendChatMessageSucess()
                }.addOnFailureListener {
                    listenerSendMessage.errorSendChatMessage(it)
                }
    }

...


override fun getAllMessageFromChatRoom(idChatRoom: String, listenerGetAllChatMessage: ListenerGetAllChatMessage) {
        Log.d(TAG, "ChatController - getAllMessageFromChatRoom")

        listenerSnapshotAllMessageFromChatRoom = chatChannelsCollectionRef

                .document(idChatRoom)
                .collection(MESSAGES)
                .orderBy("timestamp", Query.Direction.ASCENDING)
                .addSnapshotListener(object : EventListener<QuerySnapshot> {
                    override fun onEvent(querySnapshot: QuerySnapshot?, p1: FirebaseFirestoreException?) {
                        querySnapshot?.let { qSnap ->
                            if (!qSnap.isEmpty) {
                                var documentChange = qSnap.documentChanges

                                for (doc in documentChange) {
                                    var message = doc.document.toObject(Message::class.java)
                                    Log.i(TAG, "Document Change: " + message.content)
                                    listenerGetAllChatMessage.onChatMessage(message)
                                }
                            }
                        }
                    }
                })
    }