如何修改右键弹出的菜单的内容

CMenu menu;

　　ClientToScreen(&point);

　　VERIFY( menu.LoadMenu( IDR_MENU1 ) );

　　CMenu* popup = menu.GetSubMenu(0);

　　ASSERT( popup != NULL );

　　popup->EnableMenuItem(ID_POPUP1, MF_BYCOMMAND|MF_GRAYED);

　　popup->ModifyMenu(ID_POPUP1,MF_BYCOMMAND,ID_POPUP1, "11");

　　popup->TrackPopupMenu(TPM_LEFTALIGN | TPM_RIGHTBUTTON, point.x, point.y, this );