// Push this action onto the action list if we can undo it
if(undoable_action)
{
// If necessary, signal the change in status of undo
if(undo_action_stack_.empty()) signal_undo_status_(true);
// Push this action onto the action list if we can undo it
if(undoable_action)
{
// If necessary, signal the change in status of undo
if(undo_action_stack_.empty()) signal_undo_status_(true);