elseif(g.NavId==id&&g.NavMoveRequest&&g.NavMoveDir==ImGuiDir_Down)// Menu bar: Nav-Down to open
{
g.NavMoveRequest=false;
want_open=true;
}
if(!enabled)// explicitly close if an open menu becomes disabled, facilitate users code a lot in pattern such as 'if (BeginMenu("options", has_object)) { ..use object.. }'