Android service is frequently stopped and restarted

Question

I'm trying to develop an Android application which draws a floating overlay on the screen, as it is done by Facebook messenger with chat heads.

I've created an Android service from which I handle the UI. Everything works well, but on some devices the service is stopped very frequently and sometimes it is started again after more than 60 seconds.

I know this is a behavior defined by the Android System, but I was wondering if there is a way to give my service the maximum priority. Is this possible? Could this behavior be worsened by something in my implementation which is wrong?

Answer 1

One option is to make your Service a "Foreground Service" as briefly explained in Android documentation. This means that it shows an icon and possibly some status data in the status bar. Quoting:

A foreground service is a service that's considered to be something the user is actively aware of and thus not a candidate for the system to kill when low on memory. A foreground service must provide a notification for the status bar, which is placed under the "Ongoing" heading, which means that the notification cannot be dismissed unless the service is either stopped or removed from the foreground.

In practice you just need to modify the Service's onStartCommand() method to set up the notification and to call startForeGround(). This example is from the Android documentation:

// Set the icon and the initial text to be shown.
Notification notification = new Notification(R.drawable.icon, getText(R.string.ticker_text), System.currentTimeMillis());
// The pending intent is triggered when the notification is tapped.
Intent notificationIntent = new Intent(this, ExampleActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);
// 2nd parameter is the title, 3rd one is a status message.
notification.setLatestEventInfo(this, getText(R.string.notification_title), getText(R.string.notification_message), pendingIntent);
// You can put anything non-zero in place of ONGOING_NOTIFICATION_ID.
startForeground(ONGOING_NOTIFICATION_ID, notification);

That's actually a deprecated way of setting up a notification but the idea is the same anyway even if you use Notification.Builder.