DynamicCreation dxBarSubItem Menu。可动态创建dxBarSubItem，以及二级子菜单dxBarButton，并有二级子菜单关联单击事件处理。-DynamicCreation dxBarSubItem Menu. Dynamically create dxBarSubItem, as well as two sub-menus dxBarButton, and there are two sub-menus associated with the click event handler.