Added "Custom Sorting" to playlist view.

wobuzz/library/library.py

@@ -37,7 +37,13 @@ class Library:
         view = PlaylistView()
         view.setDragDropMode(QAbstractItemView.DragDropMode.InternalMove)
 
-        for track in playlist.tracks:
+        num_tracks = len(playlist.tracks)
+
+        i = 0
+
+        while i < num_tracks:
+            track = playlist.tracks[i]
+
             track_item = QTreeWidgetItem(view)
 
             track_item.setFlags(
@@ -50,6 +56,9 @@ class Library:
             track_item.setText(1, track.tags.title)
             track_item.setText(2, track.tags.artist)
             track_item.setText(3, track.tags.album)
+            track_item.setText(4, str(i + 1))
+
+            i += 1
 
         return view