Android - implementing startForeground for a service?

I'd start by completely filling in the Notification. Here is a sample project demonstrating the use of startForeground().

From your main activity, start the service with the following code:

Intent i = new Intent(context, MyService.class); context.startService(i);

Then in your service for onCreate() you would build your notification and set it as foreground like so:

Intent notificationIntent = new Intent(this, MainActivity.class);PendingIntent pendingIntent = PendingIntent.getActivity(this, 0,                notificationIntent, 0);Notification notification = new NotificationCompat.Builder(this)                .setSmallIcon(R.mipmap.app_icon)                .setContentTitle("My Awesome App")                .setContentText("Doing some work...")                .setContentIntent(pendingIntent).build();startForeground(1337, notification);

Solution for Oreo 8.1

I've encountered some problems such as RemoteServiceException because of invalid channel id with most recent versions of Android. This is how i solved it:

Activity:

override fun onCreate(savedInstanceState: Bundle?) {    val intent = Intent(this, BackgroundService::class.java)    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {        startForegroundService(intent)    } else {        startService(intent)    }}

BackgroundService:

override fun onCreate() {    super.onCreate()    startForeground()}private fun startForeground() {    val service = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager    val channelId =            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {                createNotificationChannel()            } else {                // If earlier version channel ID is not used                // https://developer.android.com/reference/android/support/v4/app/NotificationCompat.Builder.html#NotificationCompat.Builder(android.content.Context)                ""            }    val notificationBuilder = NotificationCompat.Builder(this, channelId )    val notification = notificationBuilder.setOngoing(true)            .setSmallIcon(R.mipmap.ic_launcher)            .setPriority(PRIORITY_MIN)            .setCategory(Notification.CATEGORY_SERVICE)            .build()    startForeground(101, notification)}@RequiresApi(Build.VERSION_CODES.O)private fun createNotificationChannel(): String{    val channelId = "my_service"    val channelName = "My Background Service"    val chan = NotificationChannel(channelId,            channelName, NotificationManager.IMPORTANCE_HIGH)    chan.lightColor = Color.BLUE    chan.importance = NotificationManager.IMPORTANCE_NONE    chan.lockscreenVisibility = Notification.VISIBILITY_PRIVATE    val service = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager    service.createNotificationChannel(chan)    return channelId}

JAVA EQUIVALENT

public class YourService extends Service {    // Constants    private static final int ID_SERVICE = 101;    @Override    public int onStartCommand(Intent intent, int flags, int startId) {        super.onStartCommand(intent, flags, startId);        return START_STICKY;    }    @Override    public void onCreate() {        super.onCreate();        // do stuff like register for BroadcastReceiver, etc.        // Create the Foreground Service        NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);        String channelId = Build.VERSION.SDK_INT >= Build.VERSION_CODES.O ? createNotificationChannel(notificationManager) : "";        NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this, channelId);        Notification notification = notificationBuilder.setOngoing(true)                .setSmallIcon(R.mipmap.ic_launcher)                .setPriority(PRIORITY_MIN)                .setCategory(NotificationCompat.CATEGORY_SERVICE)                .build();        startForeground(ID_SERVICE, notification);    }    @RequiresApi(Build.VERSION_CODES.O)    private String createNotificationChannel(NotificationManager notificationManager){        String channelId = "my_service_channelid";        String channelName = "My Foreground Service";        NotificationChannel channel = new NotificationChannel(channelId, channelName, NotificationManager.IMPORTANCE_HIGH);        // omitted the LED color        channel.setImportance(NotificationManager.IMPORTANCE_NONE);        channel.setLockscreenVisibility(Notification.VISIBILITY_PRIVATE);        notificationManager.createNotificationChannel(channel);        return channelId;    }}