broadcastreceiver - Run service on incoming SMS in android Oreo

Question

I'm developing an app which needs to run some code (Networking) whenever an SMS is received.
In API 25 and lower it's fine, I register an implicit receiver in Manifest file and start my service in the specified class which extended BroadcastReceiver. In API 26 however you cannot register android.provider.Telephony.SMS_RECEIVED in a receiver since it won't work.

From Android documentation:

Note: If your app targets API level 26 or higher, you cannot use the manifest to declare a receiver for implicit broadcasts (broadcasts that do not target your app specifically), except for a few implicit broadcasts that are exempted from that restriction. In most cases, you can use scheduled jobs instead.

I've read several articles like this one on medium. There are solutions like JobScheduler or Explicit Receiver, however the first one is used for changes in network state and I couldn't find a way to trigger the job on SMS_RECEIVED event and the second one is valid until your activity is up and running.

Because of the nature of my application I need to listen for incoming SMS whether the app is running or not. How to do that in API 26+?

Edit

Maybe the code in JobInfoBuilder doc on android website could help. It monitors the changes in the photos on a device and start the job on change. However I cannot find a proper Uri to do the same with the SMS (not even sure if it's possible to monitor SMS via ContentObserver)

Answer 1

Since there are lots of ways to do the job in android O, I post this answer and mention my approach to solve the problem. Obviously by problem I mean the general problem not the SMS_RECEIVED receiver itself.

I start a foreground service and in there I register a dynamic or explicit receiver to listen to the incoming calls (for instance):

In MainActivity.java:

String action = "START"
final Intent intent = new Intent(this, CallMonitorService.class);
intent.setAction(action);
startService(intent);

In CallMonitorService.javas onCreate() method where I have BroadcastReceiver callExplicitReceiver as a field:

    final IntentFilter intentFilter = new IntentFilter();
    intentFilter.setPriority(2147483647);
    intentFilter.addAction("android.intent.action.PHONE_STATE");
    this.callExplicitReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equals(TelephonyManager.ACTION_PHONE_STATE_CHANGED)) {
                // do the stuff here
            }
        }
    };
    registerReceiver(callExplicitReceiver, intentFilter);

and then in onStartCommand():

    if (intent.getAction().equals("START")) {
        Intent callServiceNotificationIntent = new Intent(this, MainActivity.class);
        callServiceNotificationIntent.setFlags(
            Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
        PendingIntent pendingIntent = PendingIntent
            .getActivity(this, CALL_SERVICE_REQUEST_CODE,
                    callServiceNotificationIntent, CALL_SERVICE_FLAG);

        Notification notification = new NotificationCompat.Builder(this)
            .setContentTitle(CALL_NOTIFICATION_CONTENT_TITLE)
            .setTicker(CALL_NOTIFICATION_TICKER)
            .setContentText(CALL_NOTIFICATION_CONTENT_TEXT)
            .setSmallIcon(R.drawable.ic_info_outline_black_24dp)
            .setContentIntent(pendingIntent)
            .setOngoing(true)
            .build();
        startForeground(CALL_NOTIFICATION_ID, notification);
    }

and finally:

@Override
public void onDestroy() {
    super.onDestroy();
    unregisterReceiver(callExplicitReceiver);
}

I think of this as a good approach since the user is notified of the running service because of the undismissable notification and that's what android Oreo wants, however through a button in the app user could stop the service and the monitoring receiver as a direct result of destroying service (I cleared that part of code).