Python (PyQt5) and signals

JasonS

I'm trying to get signals working from Python and need some help.

I have one main QML file (main.qml) with an application window and then am loading a second QML file with a pane via StackView

main.qml

import QtQuick 2.2
import QtQuick.Layouts 1.3
import QtQuick.Controls 2.0
import QtQuick.Controls.Material 2.0

ApplicationWindow{
    id: window
    width: 800
    height: 480
    visible: true
    title: "Demo"

    StackView {
        id: stackView
        anchors.fill:   parent
        initialItem: Qt.resolvedUrl("pages/Page1.qml")
    }
}

page1.qml

import QtQuick 2.6
import QtQuick.Extras 1.4
import QtQuick.Controls.Styles 1.4
import QtQuick.Controls 2.0

Pane{
    id: pane1
    width: 800
    height: 480

    property var testString: "Test works"

    function test(t)
    {
        testString = t
    }

    Text {
        id: testText
        x: 11
        y: 62
        text:  testString

        font.pixelSize: 150
    }
}

main.py

import os
import sys
import threading

from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtQml import *
from PyQt5.QtWidgets import *
from PyQt5.QtQuick import *

class Test(QObject):
    done = pyqtSignal(int)
    _running = False

    def __init__(self):
        QObject.__init__(self)
        self._running = False
        print('__init__')

    def _Test(self):
        print('_Test')
        self._running = False
        self.done.emit('Test worked')

    @pyqtSlot()
    def doTest(self):
        if not self.running:
            print('doTest')
            self._running = True
            thread = threading.Thread(target=self._Test)
            thread.start()

def main():

    app = QGuiApplication(sys.argv)

    engine = QQmlApplicationEngine()

    test = Test()
    engine.rootContext().setContextProperty('test', test)

    engine.load(QUrl("main.qml"))
    root = engine.rootObjects()[0]
    test.done.connect(root.test)
    app.exec()

if __name__ == "__main__":
    main()

The error I get is:
init
Traceback (most recent call last):
File "main.py", line 48, in <module>
main()
File "main.py", line 44, in main
test.done.connect(root.test)
AttributeError: 'QQuickWindow' object has no attribute 'test'

I understand why, but I don't know how to correct it. How do I get the test function so I can connect to it when it's in a child of mail.qml?