This event only occurs when a menu item has submenu items to display.

该事件仅在菜单项有要显示的子菜单项时发生。

youdao

Likewise, disabling a menu item that has submenu items hides the submenu items, but does not disable them.

同样地，停用功能表项目具有子功能表项目就会隐藏子功能表项目，但不停用它们。

youdao

However, menu items in the same submenu should not have identical access keys.

不过，同一子功能表中的功能表项目不得有相同的便捷键。

youdao