Question

我正在尝试使用Firebase数据库创建聊天应用。我正在阅读文档和观看教程，但有一件事我无法弄清楚该怎么做。当用户向其他用户发送消息时，使用密钥创建聊天室：＆＃34; senderUserId_receiverUserId＆＃34;
您可以在下面看到我的结构。

{
  "chat_rooms" : {
    "nTAHqCTmLRcLOM8CTfnHF4lRjLf2_oTLYaHMOMibh3ZqOcmpcWDtSCKp1" : {
      "-KtQEGK38lhZrgnNxmqb" : {
        "date" : "07/09/2017 10:28",
        "message" : “Thanks for helping !”,
        "photoUrl" : "http://www.clker.com/cliparts/B/R/Y/m/P/e/blank-profile-hi.png",
        "receiverName" : "Ali”,
        "receiverUid" : "oTLYaHMOMibh3ZqOcmpcWDtSCKp1",
        "senderName" : “John”,
        "senderUid" : "nTAHqCTmLRcLOM8CTfnHF4lRjLf2"
      },
      "-KtQEKK2BmIMzwruN-21" : {
        "date" : "07/09/2017 10:28",
        "message" : “Another Test Message“,
        "photoUrl" : "http://www.clker.com/cliparts/B/R/Y/m/P/e/blank-profile-hi.png",
        "receiverName" : “John”,
        "receiverUid" : "nTAHqCTmLRcLOM8CTfnHF4lRjLf2",
        "senderName" : "Ali",
        "senderUid" : "oTLYaHMOMibh3ZqOcmpcWDtSCKp1"
      },
      "-KtQIGDk5zE4JZuE9pIQ" : {
        "date" : "07/09/2017 10:45",
        "message" : “Test message !“,
        "photoUrl" : "http://www.clker.com/cliparts/B/R/Y/m/P/e/blank-profile-hi.png",
        "receiverName" : “John”,
        "receiverUid" : "nTAHqCTmLRcLOM8CTfnHF4lRjLf2",
        "senderName" : "Ali",
        "senderUid" : "oTLYaHMOMibh3ZqOcmpcWDtSCKp1"
      }
    }
  },
  "users" : {
    "nTAHqCTmLRcLOM8CTfnHF4lRjLf2" : {
      "address" : “istanbul”,
      "cell_phone" : “none”,
      "email" : “john@gmail.com",
      "home_phone" : “none”,
      "name" : “John”,
      "photoUrl" : "http://www.clker.com/cliparts/B/R/Y/m/P/e/blank-profile-hi.png",
      "userId" : "nTAHqCTmLRcLOM8CTfnHF4lRjLf2"
    },
    "oTLYaHMOMibh3ZqOcmpcWDtSCKp1" : {
      "address" : “istanbul”,
      "cell_phone" : “none”,
      "email" : "ali@gmail.com”,
      "home_phone" : “none”,
      "name" : "Ali",
      "photoUrl" : "http://www.clker.com/cliparts/B/R/Y/m/P/e/blank-profile-hi.png",
      "userId" : "oTLYaHMOMibh3ZqOcmpcWDtSCKp1"
    }
  }
}

通过这种方式一切正常，但我不知道如何在WhatsApp的聊天页面列出用户列表中的所有会话。我的意思是当用户点击时对话项目相关对话将会公开我发送的私信包含以下代码：

public void sendMessageToFirebaseUser(final Context context, final ChatMessageModel chat, final String receiverFirebaseToken) {

        final String room_type_1 = chat.getSenderUid() + "_" + chat.getReceiverUid();
        final String room_type_2 = chat.getReceiverUid() + "_" + chat.getSenderUid();

        final DatabaseReference databaseReference = FirebaseDatabase.getInstance().getReference();

        databaseReference.child(Constants.ARG_CHAT_ROOMS)
                .getRef()
                .addListenerForSingleValueEvent(new ValueEventListener() {
                    @Override
                    public void onDataChange(DataSnapshot dataSnapshot) {
                        if (dataSnapshot.hasChild(room_type_1)) {
                            Log.e("aaa", "sendMessageToFirebaseUser: " + room_type_1 + " exists");
                            databaseReference.child(Constants.ARG_CHAT_ROOMS)
                                    .child(room_type_1)
                                    .push()
                                    .setValue(chat);
                        } else if (dataSnapshot.hasChild(room_type_2)) {
                            Log.e("aaa", "sendMessageToFirebaseUser: " + room_type_2 + " exists");
                            databaseReference.child(Constants.ARG_CHAT_ROOMS)
                                    .child(room_type_2)
                                    .push()
                                    .setValue(chat);
                        } else {
                            Log.e("aaa", "sendMessageToFirebaseUser: success");
                            databaseReference.child(Constants.ARG_CHAT_ROOMS)
                                    .child(room_type_1)
                                    .push()
                                    .setValue(chat);
                        }
                    }

                    @Override
                    public void onCancelled(DatabaseError databaseError) {

                    }
                });
    }

感谢您阅读我的帖子。

Answer 1

如果要显示当前用户的聊天室列表，您应该对数据建模以允许这样做。最简单的方法是为每个用户添加一个聊天室列表到您的数据模型中：

"userChatrooms" : {
  "nTAHqCTmLRcLOM8CTfnHF4lRjLf2" : {
    "nTAHqCTmLRcLOM8CTfnHF4lRjLf2_oTLYaHMOMibh3ZqOcmpcWDtSCKp1": true
  },
  "oTLYaHMOMibh3ZqOcmpcWDtSCKp1" : {
    "nTAHqCTmLRcLOM8CTfnHF4lRjLf2_oTLYaHMOMibh3ZqOcmpcWDtSCKp1": true
  }
}

Firebase数据库如何从WhatsApp Chats页面等节点创建列表

1 个答案: