Hide notification of foreground service while activity is visible

android, foreground, notifications, service

Solution

You can do it like this. One prerequisite to this method is, that your activity must bind the service.

First you start service foreground.

private Notification mNotification;

public void onCreate() {
   ...
   startForeground(1, mNotification);
}

Then in your activity you bind and unbind the service as shown below. `BIND_ADJUST_WITH_ACTIVITY` is important for keeping service alive for the time it is bound to visible activity.

public void onStart() {
    ...
    Intent intent = new Intent(this, PlayerService.class);
    bindService(intent, mConnection, BIND_ADJUST_WITH_ACTIVITY);
}

public void onStop() {
    ...
    unbindService(mConnection);
}

Now here is the last past. You stop foreground, when at least one client is connected to the service, and you start foreground, when last client disconnects.

@Override
public void onRebind(Intent intent) {
    stopForeground(true); // <- remove notification
}

@Override
public IBinder onBind(Intent intent) {
    stopForeground(true); // <- remove notification
    return mBinder;
}

@Override
public boolean onUnbind(Intent intent) {
    startForeground(1, mNotification); // <- show notification again
    return true; // <- important to trigger future onRebind()
}

When binding a service, you have to consider rules applied by Android. If you bind a not started service, the service will not start automatically unless you specify `BIND_AUTO_CREATE` flag in addition to `BIND_ADJUST_WITH_ACTIVITY` flag.

    Intent intent = new Intent(this, PlayerService.class);
    bindService(intent, mConnection, BIND_AUTO_CREATE 
            | BIND_ADJUST_WITH_ACTIVITY);

If service was started with auto creation flag on, and last client unbinds then service will stop automatically. If you want to keep service running you have to start it with `startService()` method. Basically, your code will look like the one below.

    Intent intent = new Intent(this, PlayerService.class);
    startService(intent);
    bindService(intent, mConnection, BIND_ADJUST_WITH_ACTIVITY);

Calling `startService()` for already started service has no effect on it, as we do not override `onCommand()` method.

Problem

Is their a way to start a service as a foreground service and hide the notification while an activity is visible? Consider a music player, while the app is opened, you don't need the notification (with i.e. the buttons), but whenever the music player is in the background, the notification should be shown. I know, how to do this, if I DON'T run my service in foreground... But when running in foreground, the service itself needs the notification and shows it and I can't manage the notification by myself... How can I solve that problem?

Original source