Android Push notifications not working when app is closed

I'm using OkSse to subscribe to my Server Sent Events.

Whenever a new message is sent by the server, a notification should appear whether the app is in foreground,minimized or fully closed.

The notifications work as expected when minimized or in foreground but when fully closed, this only works on some device brands.

Researching a bit, I found that:

this issue is noticed only on phones by manufacturers like Xiaomi, Oppo, One Plus, Vivo, Lenovo, Huawei, Samsung, and a few others.

How does WhatsApp, Facebook, Slack, Gmail, etc.. display notifications even if app is closed?

I don't use FCM, just subscribe to Sse.

I also have in manifest:

<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

<receiver android:name="com.goparty.communication.NotificationsAlarmReceiver">
    <intent-filter>
        <action android:name="android.media.action.DISPLAY_NOTIFICATION" />
        <action android:name="android.intent.action.BOOT_COMPLETED"/>
    </intent-filter>
</receiver>

How can I achieve this?

Update

I managed to make it work by using an IntentService and BroadcastReceiver but this crashes for Oreo versions.

After more reading I found that JobIntentService is the replacement of IntentService when targeting Android O and above.

The transition to JobIntentService was pretty straight forward but again, my solution is not working when I close the app.

The whole purpose of notifications are to work even when the app is closed.

Using IntentService worked in the background by sending a broadcast with a new intent of my service.

I'm doing the same with JobIntentService with no luck.

Here's my code:

public class NotificationService extends JobIntentService {

    private static final int JOB_ID = 1;
    private NotificationManager notificationManager;

    public static void enqueueWork(Context context, Intent intent) {
        enqueueWork(context, NotificationService.class, JOB_ID, intent);
    }

    @Override
    public void onCreate() {
        super.onCreate();
        Logger.logGoParty(getClass().getSimpleName() + "#onCreate");
        notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        Logger.logGoParty("Running in background.");
        sendBroadcast(new Intent(getApplicationContext(), NotificationService.class));
    }

    @Override
    protected void onHandleWork(@NonNull Intent intent) {
        Logger.logGoParty(getClass().getSimpleName() + "#onHandleWork");
        Logger.logGoParty("Sse initialized");

        Request request = new Request.Builder().url("the sse url").build();
        OkSse okSse = new OkSse();

        ServerSentEvent sse = okSse.newServerSentEvent(request, new ServerSentEvent.Listener() {
            @Override
            public void onOpen(ServerSentEvent sse, Response response) {
                Logger.logGoParty(response.toString());
            }

            @Override
            public void onMessage(ServerSentEvent sse, String id, String event, String message) {
                Logger.logGoParty("Sse#onMessage: " + message);
                try {
                    JSONObject promoJson = new JSONObject(message);

                    sendNotification(...);

                } catch (JSONException e) {
                    Logger.logGoParty("JSONException: " + e.toString());
                }
            }
                // ...
        });
    }

    private void sendNotification(String promoImageUrl, String notificationContent, String title) {

        try {
            URL url = new URL(promoImageUrl);
            Bitmap bitmap = BitmapFactory.decodeStream(url.openConnection().getInputStream());


            NotificationCompat.BigPictureStyle style = new NotificationCompat.BigPictureStyle();
            style.bigPicture(bitmap);

            Uri defaultSound = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);

            Intent intent = new Intent(this, MapsActivity.class);
            intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP);
            intent.putExtra("page-to-open", "promotions");
            PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, 0);


            NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this, GoParty.PROMO_CHANNEL_ID)
                    .setSmallIcon(R.mipmap.ic_launcher_round)
                    .setContentTitle(title)
                    .setAutoCancel(true)
                    .setSound(defaultSound)
                    .setContentText(notificationContent)
                    .setContentIntent(pendingIntent)
                    .setStyle(style)
                    .setLargeIcon(bitmap)
                    .setWhen(System.currentTimeMillis())
                    .setPriority(NotificationCompat.PRIORITY_HIGH)
                    .setCategory(NotificationCompat.CATEGORY_MESSAGE);

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

            Log.i("GoParty", "Notification sent ----- ");

        } catch (MalformedURLException e) {
            Logger.logGoParty(e.toString());
        } catch (IOException e) {
            Logger.logGoParty(e.toString());
        }
    }
}

Notification Receiver:

public class NotificationReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {

        Intent notificationIntent = new Intent(context, NotificationService.class);
        NotificationService.enqueueWork(context, notificationIntent);
    }
}

Manifest:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.goparty">

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.WAKE_LOCK" />
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />


    <application
        android:name=".scopes.application.GoParty"
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">

        <activity
            android:name=".MapsActivity"
            android:label="@string/title_activity_maps"
            android:screenOrientation="portrait">
            <meta-data
                android:name="android.support.PARENT_ACTIVITY"
                android:value="com.goparty.LoginActivity" />
        </activity>

        <service
            android:name=".jobs.NotificationService"
            android:permission="android.permission.BIND_JOB_SERVICE" />

        <receiver android:name=".receivers.NotificationReceiver">
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED" />
            </intent-filter>
        </receiver>

    </application>

</manifest>

from Android Push notifications not working when app is closed