QML MenuBar看起来很奇怪

Question

我目前正在尝试使用PyQt和QML。我添加了一个MenuBar，但它看起来像这样：

但我想要的是标准（取决于系统）菜单栏。我的main.py代码如下所示：

import sys
import PyQt5

from PyQt5 import QtCore
from PyQt5 import QtGui
from PyQt5 import QtQml

class NovaApp(QtGui.QGuiApplication):
    """the app self"""
    def __init__(self, argv):
        super(NovaApp, self).__init__(argv)

def main(argv):
    app = NovaApp(sys.argv)

    engine = QtQml.QQmlEngine(app)

    component = QtQml.QQmlComponent(engine)
    component.loadUrl(QtCore.QUrl("qml/window.qml"))

    topLevel = component.create()

    if topLevel is not None:
        topLevel.show()
    else:
        for err in component.errors():
            print(err.toString())

    app.exec_()

if __name__ == '__main__':
    main(sys.argv)

QML文件如下所示：

import QtQuick 2.0
import QtQuick.Controls 1.2
import QtQuick.Controls.Styles 1.0
import QtQuick.Dialogs 1.0
import QtQuick.Layouts 1.0
import QtGraphicalEffects 1.0

ApplicationWindow {
    width: 800
    height: 600
    title: "Nova"

     menuBar: MenuBar {
        id: mainMenu
        Menu {
            title: "File"
            MenuItem { text: "Open..." }
            MenuItem { text: "Close" }
        }

        Menu {
            title: "Edit"
            MenuItem { text: "Cut" }
            MenuItem { text: "Copy" }
            MenuItem { text: "Paste" }
        }
    }
}

此致 扬