通过 api 显示应用程序在后台时收到的 Firebase 消息通知

Question

我已经建立了一个聊天应用程序。 它工作正常。 两个用户都可以轻松聊天，但我遇到的问题是，如果一个用户的应用程序处于后台并且屏幕关闭，则用户无法收到收到的消息的通知。

我现在想要的是在我的应用程序中，当 userA 向 userB 发送消息，并且 userB 移动空闲但应用程序在后台运行时，userB 可以获得有关该消息的通知。 userB 可以打开聊天活动并阅读消息。

My firebase notification is working from firebase console but I don't know how to call instance id and send that to particular device from api and particular user get notification about the received message, when application screen is off and application is running in background state. 我应该如何实现它？

我在这里有我的 firebase 实例 ID 服务 class ：

public class MyFirebaseInstanceIDService extends FirebaseInstanceIdService {
    private static final String TAG = "MyFirebaseIIDService";

    @Override
    public void onTokenRefresh() {

        //Getting registration token
        String refreshedToken = FirebaseInstanceId.getInstance().getToken();

        //Displaying token on logcat
        Log.d(TAG, "Refreshed token: " + refreshedToken);
    }

    private void sendRegistrationToServer(String token) {
        //You can implement this method to store the token on your server
        //Not required for current project
    }
}

这是我的 MyFirebase 消息服务 Class

public class MyFirebaseMessagingService extends FirebaseMessagingService {
    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        if (remoteMessage.getNotification().getBody() != null) {
            Log.e("FIREBASE", "Message Notification Body: " + remoteMessage.getNotification().getBody());
            sendNotification(remoteMessage);
        }
    }

    private void sendNotification(RemoteMessage remoteMessage) {
        RemoteMessage.Notification notification = remoteMessage.getNotification();
        Intent intent = new Intent(this, LoggedInView.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent,
                PendingIntent.FLAG_ONE_SHOT);

        Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
        NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
                .setLargeIcon(BitmapFactory.decodeResource(getResources(),R.drawable.first_aid))
                .setSmallIcon(R.drawable.first_aid)
                .setContentTitle(notification.getTitle())
                .setContentText(notification.getBody())
                .setAutoCancel(true)
                .setSound(defaultSoundUri)
                .setContentIntent(pendingIntent);

        NotificationManager notificationManager =
                (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

        notificationManager.notify(0, notificationBuilder.build());
    }
}

这是我的聊天活动：

public class Chat extends AppCompatActivity {
    LinearLayout layout;
    ImageView sendButton,vidcall;
    EditText messageArea;
    ScrollView scrollView;
    Firebase reference1, reference2;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.act_chat);

        layout = (LinearLayout)findViewById(R.id.layout1);
        sendButton = (ImageView)findViewById(R.id.sendButton);
        vidcall = (ImageView)findViewById(R.id.vidBtnk);
        messageArea = (EditText)findViewById(R.id.messageArea);
        scrollView = (ScrollView)findViewById(R.id.scrollView);

        Firebase.setAndroidContext(this);
        reference1 = new Firebase("https://*******.firebaseio.com/messages/" + UserDetails.username + "_" + UserDetails.chatWith);
        reference2 = new Firebase("https://*******.firebaseio.com/messages/" + UserDetails.chatWith + "_" + UserDetails.username);

        sendButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String messageText = messageArea.getText().toString();

                if(!messageText.equals("")){
                    Map<String, String> map = new HashMap<String, String>();
                    map.put("message", messageText);
                    map.put("user", UserDetails.username);
                    reference1.push().setValue(map);
                    reference2.push().setValue(map);
                }
                messageArea.setText("");
            }
        });

        vidcall.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {


                startActivity(new Intent(Chat.this, ConnectActivity.class));



            }
        });

        reference1.addChildEventListener(new ChildEventListener() {
            @Override
            public void onChildAdded(DataSnapshot dataSnapshot, String s) {
                Map map = dataSnapshot.getValue(Map.class);
                String message = map.get("message").toString();
                String userName = map.get("user").toString();

                if(userName.equals(UserDetails.username)){
                    addMessageBox("You:-\n" + message, 1);
                }
                else{
                    addMessageBox(UserDetails.chatWith + ":-\n" + message, 2);
                }
            }

            @Override
            public void onChildChanged(DataSnapshot dataSnapshot, String s) {

            }

            @Override
            public void onChildRemoved(DataSnapshot dataSnapshot) {

            }

            @Override
            public void onChildMoved(DataSnapshot dataSnapshot, String s) {

            }

            @Override
            public void onCancelled(FirebaseError firebaseError) {

            }
        });
    }


   // boolean doubleBackToExitPressedOnce = false;

    @Override
    public void onBackPressed() {

        AlertDialog.Builder builder1 = new AlertDialog.Builder(Chat.this);
        builder1.setMessage("CAUTION! -> Do Wish to End this Session");
        builder1.setCancelable(true);
        builder1.setPositiveButton(
                "Yes",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {

                        finish();

                        dialog.cancel();
                    }
                });

        builder1.setNegativeButton(
                "No",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {
                        dialog.cancel();
                    }
                });

        AlertDialog alert11 = builder1.create();
        alert11.show();


    }


    public void addMessageBox(String message, int type){
        TextView textView = new TextView(Chat.this);
        textView.setText(message);
        LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
        lp.setMargins(0, 0, 0, 10);
        textView.setLayoutParams(lp);

        if(type == 1) {
            textView.setBackgroundResource(R.drawable.rounded_corner1);
        }
        else{
            textView.setBackgroundResource(R.drawable.rounded_corner2);
        }

        layout.addView(textView);
        scrollView.fullScroll(View.FOCUS_DOWN);
    }
}

Answer 1

您需要在后台运行的服务才能捕获PUSH通知并将其显示给用户，这就是Firebase通知服务为您提供的功能。 我有这个（你必须修改它，以便在出现通知时做你想做的事）：

public class MyFirebaseMessagingService extends FirebaseMessagingService {

    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        if (remoteMessage.getNotification().getBody() != null) {
            Log.e("FIREBASE", "Message Notification Body: " + remoteMessage.getNotification().getBody());
            sendNotification(remoteMessage);
        }
    }

    private void sendNotification(RemoteMessage remoteMessage) {
        RemoteMessage.Notification notification = remoteMessage.getNotification();
        Intent intent = new Intent(this, MainActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent,
                PendingIntent.FLAG_ONE_SHOT);

        Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
        NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
                .setLargeIcon(BitmapFactory.decodeResource(getResources(),R.drawable.logo_gris))
                .setSmallIcon(R.drawable.logo_gris)
                .setContentTitle(notification.getTitle())
                .setContentText(notification.getBody())
                .setAutoCancel(true)
                .setSound(defaultSoundUri)
                .setContentIntent(pendingIntent);

        NotificationManager notificationManager =
                (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

        notificationManager.notify(0, notificationBuilder.build());
    }


}

Answer 2

我解决了这个问题可能对某人有帮助，

为了通过api向单个设备发送firebase的通知如下：

1：生成实例ID，对每个设备都是唯一的

public class MyFirebaseInstanceIDService extends FirebaseInstanceIdService {
private static final String TAG = "MyFirebaseIIDService";

@Override
public void onTokenRefresh() {

    //Getting registration token
    String refreshedToken = FirebaseInstanceId.getInstance().getToken();

    //Displaying token on logcat
    Log.d(TAG, "Refreshed token: " + refreshedToken);

    sendRegistrationToServer(refreshedToken);

}

private void sendRegistrationToServer(String token) {
    //You can implement this method to store the token on your server
    //Not required for current project




}

}

注意：您可以从应用程序的任何位置调用Instance Id，如下所示：

String tkn = FirebaseInstanceId.getInstance().getToken();
        Toast.makeText(Doc_users.this, "Current token ["+tkn+"]",
                Toast.LENGTH_LONG).show();
        Log.d("App", "Token ["+tkn+"]");

此令牌必须用于向单个设备发送通知，它是您可以将其存储在firebase数据库中的设备的ID

 reference.child(UserDetails.username).child("token").setValue(tokun);

2：现在您可以构建逻辑来获取这些ID并构建您的请求

public static String makeRequest(String id) throws JSONException {
        HttpURLConnection urlConnection;
        JSONObject json = new JSONObject();
        JSONObject info = new JSONObject();
        info.put("title", "Notification Title");   // Notification title
        info.put("body", "Notification body"); // Notification body
        info.put("sound", "mySound"); // Notification sound
        json.put("notification", info);
        json.put("to","INSTANCE ID FETCHED FOR SIGNLE DEVICE HERE");
        Log.e("deviceidkey==> ",id+"");
        Log.e("jsonn==> ",json.toString());
        String data = json.toString();
        String result = null;
        try {
            //Connect
            urlConnection = (HttpURLConnection) ((new URL("https://fcm.googleapis.com/fcm/send").openConnection()));
            urlConnection.setDoOutput(true);
            urlConnection.setRequestProperty("Content-Type", "application/json");
            urlConnection.setRequestProperty("Authorization", "key=YOUR FIREBASE SERVER KEY");
            urlConnection.setRequestMethod("POST");
            urlConnection.connect();

            //Write
            OutputStream outputStream = urlConnection.getOutputStream();
            BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
            writer.write(data);
            writer.close();
            outputStream.close();

            //Read
            BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream(), "UTF-8"));

            String line = null;
            StringBuilder sb = new StringBuilder();

            while ((line = bufferedReader.readLine()) != null) {
                sb.append(line);
            }

            bufferedReader.close();
            result = sb.toString();

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }

通知将在您的设备发送的单个设备上生成，您可以调试以放置您自己的设备密钥并使用邮递员获得有效请求：祝您好运

Answer 3

嗨，我使用firebase消息传递实现了聊天应用程序。

这里是您可以实施的步骤

1）实现sendRegistrationToServer（String token）{对后端服务器中生成的存储令牌进行异步调用（使用令牌生成的地图用户）}

2）在聊天活动中，sendmessage（）应该向服务器发送消息给secondUser（）

3）通过查看usertoken，我们应该将通知从后端服务器推送到firebase服务器。

4）实现onMessageReceived（）以显示通知

Answer 4

需要在firebase通知数据集中设置click_action才能从后台接收数据，实现onMessageReceived处理前台数据

在此处查看更新的答案： https://stackoverflow.com/a/73724040/7904082