add seek bar support

app/src/main/java/ch/blinkenlights/android/vanilla/MediaSessionTracker.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2021 Adrian Ulrich <adrian@blinkenlights.ch>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package ch.blinkenlights.android.vanilla;
+
+import android.support.v4.media.session.MediaSessionCompat;
+import android.support.v4.media.session.PlaybackStateCompat;
+import android.support.v4.media.MediaMetadataCompat;
+
+
+// Helper class used to show the notification seekbar.
+public class MediaSessionTracker {
+	/**
+	 * Instance of Vanillas PlaybackService
+	 */
+	private PlaybackService mPlaybackService;
+	/**
+	 * Our generic MediaSession
+	 */
+	private MediaSessionCompat mMediaSession;
+
+
+	MediaSessionTracker(PlaybackService service) {
+		mPlaybackService = service;
+
+		mMediaSession = new MediaSessionCompat(service, "Vanilla Music Media Session");
+		mMediaSession.setCallback(new MediaSessionCompat.Callback() {
+				@Override
+				public void onSeekTo(long pos) {
+					mPlaybackService.seekToPosition((int)pos);
+				}
+			});
+	}
+
+	/**
+	 * Returns the session token of the media session.
+	 */
+	public MediaSessionCompat.Token getSessionToken() {
+		return mMediaSession.getSessionToken();
+	}
+
+	/**
+	 * Cleans up the underlying media session
+	 */
+	public void release() {
+		mMediaSession.release();
+	}
+
+	/**
+	 * Populates the active media session with new info.
+	 */
+	public void updateSession(Song song, int state) {
+		boolean playing = (state & PlaybackService.FLAG_PLAYING) != 0;
+
+		PlaybackStateCompat playbackState = new PlaybackStateCompat.Builder()
+			.setActions(PlaybackStateCompat.ACTION_SEEK_TO)
+			.setState(playing ? PlaybackStateCompat.STATE_PLAYING : PlaybackStateCompat.STATE_PAUSED,
+					  mPlaybackService.getPosition(), 1.0f)
+			.build();
+		mMediaSession.setPlaybackState(playbackState);
+		if (song != null) {
+			mMediaSession.setMetadata(new MediaMetadataCompat.Builder()
+									  .putLong(MediaMetadataCompat.METADATA_KEY_DURATION, song.duration)
+									  .build());
+		}
+	}
+}

app/src/main/java/ch/blinkenlights/android/vanilla/PlaybackService.java

@@ -340,6 +340,11 @@ public final class PlaybackService extends Service
 	 */
 	private RemoteControl.Client mRemoteControlClient;
 
+	/**
+	 * Media session state tracker for notification
+	 */
+	private MediaSessionTracker mMediaSessionTracker;
+
 	SongTimeline mTimeline;
 	private Song mCurrentSong;
 
@@ -497,6 +502,8 @@ public final class PlaybackService extends Service
 		mRemoteControlClient = new RemoteControl().getClient(this);
 		mRemoteControlClient.initializeRemote();
 
+		mMediaSessionTracker = new MediaSessionTracker(this);
+
 		int syncMode = Integer.parseInt(settings.getString(PrefKeys.PLAYLIST_SYNC_MODE, PrefDefaults.PLAYLIST_SYNC_MODE));
 		boolean exportRelativePaths = settings.getBoolean(PrefKeys.PLAYLIST_EXPORT_RELATIVE_PATHS, PrefDefaults.PLAYLIST_EXPORT_RELATIVE_PATHS);
 		String syncFolder = settings.getString(PrefKeys.PLAYLIST_SYNC_FOLDER, PrefDefaults.PLAYLIST_SYNC_FOLDER);
@@ -646,6 +653,9 @@ public final class PlaybackService extends Service
 		if (mRemoteControlClient != null)
 			mRemoteControlClient.unregisterRemote();
 
+		if (mMediaSessionTracker != null)
+			mMediaSessionTracker.release();
+
 		super.onDestroy();
 	}
 
@@ -1106,6 +1116,7 @@ public final class PlaybackService extends Service
 			triggerReadAhead();
 
 		mRemoteControlClient.updateRemote(mCurrentSong, mState, mForceNotificationVisible);
+		mMediaSessionTracker.updateSession(mCurrentSong, mState);
 
 		scrobbleBroadcast();
 	}
@@ -1649,6 +1660,7 @@ public final class PlaybackService extends Service
 			break;
 		case MSG_BROADCAST_SEEK:
 			mRemoteControlClient.updateRemote(mCurrentSong, mState, mForceNotificationVisible);
+			mMediaSessionTracker.updateSession(mCurrentSong, mState);
 			break;
 		default:
 			return false;
@@ -2155,7 +2167,8 @@ public final class PlaybackService extends Service
 													 getString(R.string.play_pause), PendingIntent.getService(this, 0, playPause, 0)))
 			.addAction(new NotificationCompat.Action(R.drawable.next,
 													 getString(R.string.next_song), PendingIntent.getService(this, 0, next, 0)))
-			.setStyle(new androidx.media.app.NotificationCompat.MediaStyle())
+			.setStyle(new androidx.media.app.NotificationCompat.MediaStyle()
+					  .setMediaSession(mMediaSessionTracker.getSessionToken()))
 			.build();
 		return n;
 	}