Minor fixes

ultrasonic/src/main/java/org/moire/ultrasonic/receiver/MediaButtonIntentReceiver.java

@@ -25,6 +25,7 @@ import android.os.Build;
 import android.os.Bundle;
 import android.os.Parcelable;
 import android.util.Log;
+import android.view.KeyEvent;
 
 import org.moire.ultrasonic.service.DownloadServiceImpl;
 import org.moire.ultrasonic.util.Util;
@@ -62,16 +63,36 @@ public class MediaButtonIntentReceiver extends BroadcastReceiver
 			try
 			{
 				context.startService(serviceIntent);
+			}
+			catch (IllegalStateException exception)
+			{
+				Log.i(TAG, "MediaButtonIntentReceiver couldn't start DownloadServiceImpl because the application was in the background.");
+				if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
+				{
+					KeyEvent keyEvent = (KeyEvent) event;
+					if (keyEvent.getAction() == KeyEvent.ACTION_DOWN && keyEvent.getRepeatCount() == 0)
+					{
+						int keyCode = keyEvent.getKeyCode();
+						if (keyCode == KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE ||
+								keyCode == KeyEvent.KEYCODE_HEADSETHOOK ||
+								keyCode == KeyEvent.KEYCODE_MEDIA_PLAY)
+						{
+							// TODO: The only time it is OK to start DownloadServiceImpl as a foreground service is when we now it will display its notification.
+							// When DownloadServiceImpl is refactored to a proper foreground service, this can be removed.
+							context.startForegroundService(serviceIntent);
+							Log.i(TAG, "MediaButtonIntentReceiver started DownloadServiceImpl as foreground service");
+						}
+					}
+				}
+			}
 
+			try
+			{
 				if (isOrderedBroadcast())
 				{
 					abortBroadcast();
 				}
 			}
-			catch (IllegalStateException exception)
-			{
-				Log.w(TAG, "MediaButtonIntentReceiver couldn't start DownloadServiceImpl because the application was in the background.");
-			}
 			catch (Exception x)
 			{
 				// Ignored.

ultrasonic/src/main/java/org/moire/ultrasonic/service/DownloadServiceImpl.java

@@ -752,6 +752,7 @@ public class DownloadServiceImpl extends Service implements DownloadService
 			if (tabInstance != null)
 			{
 				stopForeground(true);
+				clearRemoteControl();
 				isInForeground = false;
 				tabInstance.hideNowPlaying();
 			}
@@ -1277,6 +1278,7 @@ public class DownloadServiceImpl extends Service implements DownloadService
 			if (tabInstance != null)
 			{
 				stopForeground(true);
+				clearRemoteControl();
 				isInForeground = false;
 				tabInstance.hideNowPlaying();
 			}

ultrasonic/src/main/java/org/moire/ultrasonic/service/DownloadServiceLifecycleSupport.java

@@ -289,6 +289,7 @@ public class DownloadServiceLifecycleSupport
 			return;
 		}
 		Log.i(TAG, "Deserialized currentPlayingIndex: " + state.currentPlayingIndex + ", currentPlayingPosition: " + state.currentPlayingPosition);
+		// TODO: here the autoPlay = false creates problems when Ultrasonic is started by a Play MediaButton as the player won't start this way.
 		downloadService.restore(state.songs, state.currentPlayingIndex, state.currentPlayingPosition, false, false);
 
 		// Work-around: Serialize again, as the restore() method creates a serialization without current playing info.
@@ -321,7 +322,11 @@ public class DownloadServiceLifecycleSupport
 				downloadService.stop();
 				break;
 			case KeyEvent.KEYCODE_MEDIA_PLAY:
-				if (downloadService.getPlayerState() != PlayerState.STARTED)
+				if (downloadService.getPlayerState() == PlayerState.IDLE)
+				{
+					downloadService.play();
+				}
+				else if (downloadService.getPlayerState() != PlayerState.STARTED)
 				{
 					downloadService.start();
 				}