android聊天应用程序在后台时如何接收消息作为通知

Question

我正在开发一个 android 即时聊天应用程序。我已经使用 socket.io-client 库实现了它。这里一切正常。当应用程序将由不同设备上的不同用户使用时，可以使用套接字将消息从一个用户发送到另一个用户。但这只有在应用程序处于活动状态。如果应用程序在另一端未处于活动状态，则它无法正常工作。我想像 WatsApp 一样通知用户消息已到达。我如何使用套接字来实现这一点。

以下是我的 Listener 的代码：

 mSocket.on("send:notice", onReceive); // Listening event for receiving messages

 // Event Listener for receiving messages
private Emitter.Listener onReceive = new Emitter.Listener() {
    @Override
    public void call(final Object... args) {
        Log.e("Receive", "Bean_Message received");
        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                JSONObject data = (JSONObject) args[0];
                Log.e("DATA", String.valueOf(data));
                try {
                    JSONArray ops = data.getJSONArray("ops");
                    Log.e("JSONArray", ops.toString());
                    for (int i = 0; i < ops.length(); i++) {
                        JSONObject object = ops.getJSONObject(i);
                        String roomID = object.getString("room_id");
                        Log.e("RoomID", roomID); // Getting room ID from JSON array
                        Log.e("Md5RoomID", md5StringRoomID); // Getting room id which we have created using logged in user ID and room id of the user through which chat has to be done
                        //Comparing the room IDs
                        if (md5StringRoomID.equals(roomID)) {
                            String senderName = object.getString("user");
                            Log.e("Sender Name", senderName);
                            String senderID = object.getString("id");
                            Log.e("SenderID", senderID);
                            String date = object.getString("date"); // Getting timestamp value in the form of string
                            long time = Long.parseLong(date); //Converting String into long
                            String t = getDateFromTimestamp(time); // Getting date and time from timestamp
                            Log.e("DateReceived", date);
                            // JSONObject message = object.getJSONObject("message");
                            String unicodeMessageReceived = object.getString("message");
                            Log.e("UnicodeMessageReceived", unicodeMessageReceived);
                            //Decoding unicode characters for emoji
                            String messageReceived = StringEscapeUtils.unescapeJava(unicodeMessageReceived);
                            Log.e("DecodedMessageReceived", messageReceived);
                            String loggedInUSerNAme = sharedPreferences.getString(Prefs_Registration.get_user_name, null);
                            //String loggedInUSerNAme = almaChatDatabase.getUserName();
                            //If the message is sent by the owner to other from webapp ,then we need to check whether the sender is the loggedinUSer in the App or not and we will right align the messages .
                            if (loggedInUSerNAme.equalsIgnoreCase(senderName)) {
                                isSelf = true;
                                msg = new Bean_Message(senderName, messageReceived, isSelf);
                                msg.setMessageStatus(Status.SENT);
                                msg.setTime(t);
                                listBeanMessages.add(msg);
                                // Log.e("List Elements", String.valueOf(listBeanMessages));
                                adapter_message.notifyDataSetChanged();
                                playBeep();
                            } else {
                                isSelf = false;
                                msg = new Bean_Message(senderName, messageReceived, isSelf);
                                msg.setTime(t);
                                listBeanMessages.add(msg);
                                Log.e("List Elements", String.valueOf(listBeanMessages));
                                adapter_message.notifyDataSetChanged();
                                playBeep();
                            }
                        }
                    }
                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        });
    }

    // Playing sound when the message is sent by other
    public void playBeep() {
        try {
            Uri notification = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
            Ringtone r = RingtoneManager.getRingtone(getApplicationContext(), notification);
            r.play();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

};

我必须处理两种通知情况： 1.当应用程序在后台时 2. 当应用程序在前台，但是当用户C的消息到达时，用户A正忙于用户B。

请帮我解决我的问题。

Answer 1

1. 一种方法是 当您的应用程序启动时，您应该使用 START_STICKY 运行您自己的服务，并且在该服务内您必须启动一个线程。供参考请参考服务http://developer.android.com/intl/es/reference/android/app/Service.html的android文档

2. 另一种方法是使用 MQTT OR Socket AND FCM 推送通知。

• 连接socket.io服务器或MQTT协议服务器 如果用户打开应用程序建立连接并订阅事件并在用户离开后断开连接 来自 socket.io 服务器或 MQTT 的后台。
• 如果用户与 socket.io 服务器断开连接或 MQTT 回退到 FCM 推送通知，则通知用户为 FMC 和 socket.io 或 MQTT 保留相同的通知 ID，以便您可以在期间忽略其中一个处理中。

Answer 2

按照此处http://developer.android.com/guide/components/bound-services.html 的描述创建后台服务， 写入此服务中的套接字连接代码并从启动器活动启动服务并通过从其他活动绑定到服务来使用该服务

Answer 3

试试这个：

public Emitter.Listener handleIncomingMessages = new Emitter.Listener() {
    @Override
    public void call(final Object... args) {
        getActivity().runOnUiThread(new Runnable() {
            @Override
            public void run() {
                JSONObject data = (JSONObject) args[0];
                String message = null;
                String imageText;
                try {
                    message = data.getString("message").toString();
                  Log.v("messageeeeeeeeeee",message);

                } catch (JSONException e) {
                    // return;
                }

                addMessage(message);

                try {
                    imageText = data.getString("image");
                    addImage(decodeImage(imageText));
                } catch (JSONException e) {
                    //retur
                }
            }
        });
    }
};