Fixed null pointer exception when no songs are present in the

device's library.

src/org/kreed/vanilla/PlaybackService.java

@@ -565,7 +565,10 @@ public final class PlaybackService extends Service implements Handler.Callback,
 
 		Song song = mTimeline.shiftCurrentSong(delta);
 		if (song == null) {
-			setFlag(FLAG_NO_MEDIA);
+			if (Song.isSongAvailable())
+				setCurrentSong(+1); // we only encountered a bad song; skip it
+			else
+				setFlag(FLAG_NO_MEDIA); // we don't have any songs : /
 			return;
 		} else if ((mState & FLAG_NO_MEDIA) != 0) {
 			unsetFlag(FLAG_NO_MEDIA);

src/org/kreed/vanilla/Song.java

@@ -59,6 +59,10 @@ public class Song implements Parcelable {
 	 */
 	private static final Song[] mRandomSongs = new Song[5];
 
+	private static final String[] EMPTY_PROJECTION = {
+		MediaStore.Audio.Media._ID,
+		};
+
 	private static final String[] FILLED_PROJECTION = {
 		MediaStore.Audio.Media._ID,
 		MediaStore.Audio.Media.DATA,
@@ -109,11 +113,11 @@ public class Song implements Parcelable {
 		ContentResolver resolver = ContextApplication.getContext().getContentResolver();
 		Uri media = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
 		String selection = MediaStore.Audio.Media.IS_MUSIC + "!=0";
-		Cursor cursor = resolver.query(media, FILLED_PROJECTION, selection, null, null);
+		Cursor cursor = resolver.query(media, EMPTY_PROJECTION, selection, null, null);
 
 		return cursor != null && cursor.getCount() > 0;
 	}
-	
+
 	/**
 	 * Returns a song randomly selected from all the songs in the Android
 	 * MediaStore.
@@ -420,4 +424,4 @@ public class Song implements Parcelable {
 
 		return null;
 	}
-}
+}

src/org/kreed/vanilla/SongTimeline.java

@@ -273,11 +273,11 @@ public final class SongTimeline {
 	/**
 	 * Returns the song <code>delta</code> places away from the current
 	 * position. If there is no song at the given position, a random
-	 * song will be placed in that position. Returns null if no songs are
+	 * song will be placed in that position. Returns null if there is a problem
-	 * available.
+	 * retrieving the song (caused by either an empty library or stale song id).
 	 *
 	 * Note: This returns songs based on their position in the playback
-	 * sequence, not necessarily the stored timeline. When repeat is enabled,
+	 * sequence, not their position in the stored timeline. When repeat is enabled,
 	 * the two will differ.
 	 *
 	 * @param delta The offset from the current position. Should be -1, 0, or
@@ -285,28 +285,24 @@ public final class SongTimeline {
 	 */
 	public Song getSong(int delta)
 	{
-		if (!Song.isSongAvailable())
-			return null;
-		
 		ArrayList<Song> timeline = mSongs;
-		Song song;
+		Song song = null;
 
 		synchronized (this) {
 			int pos = mCurrentPos + delta;
 			if (pos < 0)
 				return null;
 
-			int size = timeline.size();
+			while (pos >= timeline.size()) {
-			if (pos > size)
-				return null;
-
-			if (pos == size) {
 				song = Song.randomSong();
+				if (song == null)
+					return null;
 				timeline.add(song);
-			} else {
-				song = timeline.get(pos);
 			}
 
+			if (song == null)
+				song = timeline.get(pos);
+
 			if (song != null && mRepeatStart != -1 && (song.flags & Song.FLAG_RANDOM) != 0) {
 				if (delta == 1 && mRepeatStart < mCurrentPos + 1) {
 					// We have reached a non-user-selected song; this song will
@@ -336,15 +332,9 @@ public final class SongTimeline {
 			}
 		}
 
-		if (song == null)
+		if (!song.query(false))
+			// we have a stale song id
 			return null;
-		
-		if (!song.query(false)) {
-			song.copy(Song.randomSong());
-			
-			if (song == null || !song.query(false))
-				return null;
-		}
 
 		return song;
 	}