/* catch changes */
tr->playlist()->LayeringChanged.connect (playlist_connections, invalidator (*this), boost::bind (&StreamView::playlist_layered, this, boost::weak_ptr<Track> (tr)), gui_context());
tr->playlist()->RegionAdded.connect (playlist_connections, invalidator (*this), boost::bind (&StreamView::add_region_view, this, _1), gui_context());
tr->playlist()->RegionRemoved.connect (playlist_connections, invalidator (*this), boost::bind (&StreamView::remove_region_view, this, _1), gui_context());
/* catch changes */
tr->playlist()->LayeringChanged.connect (playlist_connections, invalidator (*this), boost::bind (&StreamView::playlist_layered, this, boost::weak_ptr<Track> (tr)), gui_context());
tr->playlist()->RegionAdded.connect (playlist_connections, invalidator (*this), boost::bind (&StreamView::add_region_view, this, _1), gui_context());
tr->playlist()->RegionRemoved.connect (playlist_connections, invalidator (*this), boost::bind (&StreamView::remove_region_view, this, _1), gui_context());