group->Event.connect (sigc::mem_fun (*this, &TimeAxisViewItem::canvas_group_event));
//Config->ParameterChanged.connect (*this, invalidator (*this), boost::bind (&TimeAxisViewItem::parameter_changed, this, _1), gui_context ());
group->Event.connect (sigc::mem_fun (*this, &TimeAxisViewItem::canvas_group_event));
//Config->ParameterChanged.connect (*this, invalidator (*this), boost::bind (&TimeAxisViewItem::parameter_changed, this, _1), gui_context ());