Try to bind to PlayerService when MainActivity starts

Fixes mini-player not appearing on app start if the player service is already playing something.

The PlayerService (and the player) may be started from an external intent that does not involve the MainActivity (e.g. RouterActivity or Android Auto's media browser interface).
This PR tries to bind to the PlayerService as soon as the MainActivity starts, but only does so in a passive way, i.e. if the service is not already running it is not started.
Once the connection between PlayerHolder and PlayerService is setup, the ACTION_PLAYER_STARTED broadcast is sent to MainActivity so that it can setup the bottom mini-player.
Another important thing this commit does is to check whether the player is open before actually adding the mini-player view, since the PlayerService could be bound even without a running player (e.g. Android Auto's media browser is being used). This is a consequence of commit "Drop some assumptions on how PlayerService is started and reused".

Author: Stypox

app/src/main/java/org/schabi/newpipe/MainActivity.java

@@ -848,7 +848,8 @@ private void openMiniPlayerUponPlayerStarted() {
                 @Override
                 public void onReceive(final Context context, final Intent intent) {
                     if (Objects.equals(intent.getAction(),
-                            VideoDetailFragment.ACTION_PLAYER_STARTED)) {
+                            VideoDetailFragment.ACTION_PLAYER_STARTED)
+                            && PlayerHolder.getInstance().isPlayerOpen()) {
                         openMiniPlayerIfMissing();
                         // At this point the player is added 100%, we can unregister. Other actions
                         // are useless since the fragment will not be removed after that.
@@ -860,6 +861,10 @@ public void onReceive(final Context context, final Intent intent) {
             final IntentFilter intentFilter = new IntentFilter();
             intentFilter.addAction(VideoDetailFragment.ACTION_PLAYER_STARTED);
             registerReceiver(broadcastReceiver, intentFilter);
+
+            // If the PlayerHolder is not bound yet, but the service is running, try to bind to it.
+            // Once the connection is established, the ACTION_PLAYER_STARTED will be sent.
+            PlayerHolder.getInstance().tryBindIfNeeded(this);
         }
     }
 

app/src/main/java/org/schabi/newpipe/player/helper/PlayerHolder.java

@@ -22,6 +22,7 @@
 import org.schabi.newpipe.player.event.PlayerServiceEventListener;
 import org.schabi.newpipe.player.event.PlayerServiceExtendedEventListener;
 import org.schabi.newpipe.player.playqueue.PlayQueue;
+import org.schabi.newpipe.util.NavigationHelper;
 
 public final class PlayerHolder {
 
@@ -121,6 +122,9 @@ private Context getCommonContext() {
 
     public void startService(final boolean playAfterConnect,
                              final PlayerServiceExtendedEventListener newListener) {
+        if (DEBUG) {
+            Log.d(TAG, "startService() called with playAfterConnect=" + playAfterConnect);
+        }
         final Context context = getCommonContext();
         setListener(newListener);
         if (bound) {
@@ -182,23 +186,39 @@ public void onServiceConnected(final ComponentName compName, final IBinder servi
                 listener.onServiceConnected(player, playerService, playAfterConnect);
             }
             startPlayerListener();
+
+            // notify the main activity that binding the service has completed, so that it can
+            // open the bottom mini-player
+            NavigationHelper.sendPlayerStartedEvent(localBinder.getService());
         }
     }
 
     private void bind(final Context context) {
         if (DEBUG) {
             Log.d(TAG, "bind() called");
         }
-
-        final Intent serviceIntent = new Intent(context, PlayerService.class);
-        serviceIntent.setAction(PlayerService.BIND_PLAYER_HOLDER_ACTION);
-        bound = context.bindService(serviceIntent, serviceConnection,
-                Context.BIND_AUTO_CREATE);
+        // BIND_AUTO_CREATE starts the service if it's not already running
+        bound = bind(context, Context.BIND_AUTO_CREATE);
         if (!bound) {
             context.unbindService(serviceConnection);
         }
     }
 
+    public void tryBindIfNeeded(final Context context) {
+        if (!bound) {
+            // flags=0 means the service will not be started if it does not already exist. In this
+            // case the return value is not useful, as a value of "true" does not really indicate
+            // that the service is going to be bound.
+            bind(context, 0);
+        }
+    }
+
+    private boolean bind(final Context context, final int flags) {
+        final Intent serviceIntent = new Intent(context, PlayerService.class);
+        serviceIntent.setAction(PlayerService.BIND_PLAYER_HOLDER_ACTION);
+        return context.bindService(serviceIntent, serviceConnection, flags);
+    }
+
     private void unbind(final Context context) {
         if (DEBUG) {
             Log.d(TAG, "unbind() called");