如何在qml中制作带有子菜单的菜单？

import QtQuick 2.0
import QtQuick.Controls 2.0

ApplicationWindow {
    visible: true
    width: 400
    height: 300
    title: "Menu Example"

    MenuBar {
        Menu {
            title: "File"

            MenuItem {
                text: "New"
            }

            MenuItem {
                text: "Open"
            }

            Menu {
                title: "Recent Files"

                MenuItem {
                    text: "File 1"
                }

                MenuItem {
                    text: "File 2"
                }
            }

            MenuItem {
                text: "Save"
            }

            MenuItem {
                text: "Exit"
            }
        }
    }
}