如何“通过引用"将 SwipeView 的 currentIndex 设置为 TabBar 的 currentIndex转到特定页面后?

The following code is the best I've come up with. It correctly goes to the second page, and when I change the current page with the TabBar the SwipeView still updates. However, swiping to a new page no longer updates the TabBar. It appears that setting tabBar.currentIndex to swipeView.currentIndex only has the effect of setting by reference when done with the colon to initialize. Doing so with an equals sign sets by value. How can I move to a specific page while still maintaining the invariant that swipeView.currentIndex == tabBar.currentIndex?

// main.qml
import QtQuick 2.7
import QtQuick.Controls 2.0
import QtQuick.Layouts 1.0

ApplicationWindow {
    visible: true
    width: 640
    height: 480
    title: qsTr("Hello World")
    SwipeView {
        id: swipeView
        anchors.fill: parent
        currentIndex: tabBar.currentIndex

        Page {
            Button {
                text: qsTr("Continue to Page 2")
                onClicked: {
                    tabBar.currentIndex = 1;
                    // this next line merely sets tabBar.currentIndex to 1
                    tabBar.currentIndex = swipeView.currentIndex
                }
                anchors.centerIn: parent
                width: text.implicitWidth
                height: text.implicitHeight
            }
        }

        Page {
            Label {
                text: qsTr("Second page")
                anchors.centerIn: parent
            }
        }
    }

    footer: TabBar {
        id: tabBar
        currentIndex: swipeView.currentIndex
        TabButton {
            text: qsTr("First")
        }
        TabButton {
            text: qsTr( "Second")
        }
    }
}

C++ 代码只是 Qt Creator 为我提供的默认代码:

// main.cpp
#include <QGuiApplication>
#include <QQmlApplicationEngine>

int main(int argc, char *argv[])
{
    QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
    QGuiApplication app(argc, argv);

    QQmlApplicationEngine engine;
    engine.load(QUrl(QLatin1String("qrc:/main.qml")));

    return app.exec();
}

Button {
    onClicked: tabBar.setCurrentIndex(1)
}