main.cpp Example File

standalone/main.cpp
/****************************************************************************
**
** Copyright (C) 2014 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Milian Wolff <milian.wolff@kdab.com>
** Contact: http://www.qt.io/licensing/
**
** This file is part of the QtWebChannel module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL21$
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** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
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** information use the contact form at http://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 or version 3 as published by the Free
** Software Foundation and appearing in the file LICENSE.LGPLv21 and
** LICENSE.LGPLv3 included in the packaging of this file. Please review the
** following information to ensure the GNU Lesser General Public License
** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** As a special exception, The Qt Company gives you certain additional
** rights. These rights are described in The Qt Company LGPL Exception
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****************************************************************************/

#include "qwebchannel.h"

#include <QApplication>
#include <QDialog>
#include <QVariantMap>
#include <QDesktopServices>
#include <QUrl>
#include <QDir>
#include <QFileInfo>
#include <QtWebSockets/QWebSocketServer>

#include "../shared/websocketclientwrapper.h"
#include "../shared/websockettransport.h"

#include "ui_dialog.h"

/*!
    An instance of this class gets published over the WebChannel and is then accessible to HTML clients.
*/
class Dialog : public QObject
{
    Q_OBJECT

public:
    explicit Dialog(QObject *parent = 0)
        : QObject(parent)
    {
        ui.setupUi(&dialog);
        dialog.show();

        connect(ui.send, SIGNAL(clicked()), SLOT(clicked()));
    }

    void displayMessage(const QString &message)
    {
        ui.output->appendPlainText(message);
    }

signals:
    /*!
        This signal is emitted from the C++ side and the text displayed on the HTML client side.
    */
    void sendText(const QString &text);

public slots:
    /*!
        This slot is invoked from the HTML client side and the text displayed on the server side.
    */
    void receiveText(const QString &text)
    {
        displayMessage(tr("Received message: %1").arg(text));
    }

private slots:
    /*!
        Note that this slot is private and thus not accessible to HTML clients.
    */
    void clicked()
    {
        const QString text = ui.input->text();

        if (text.isEmpty()) {
            return;
        }

        emit sendText(text);
        displayMessage(tr("Sent message: %1").arg(text));

        ui.input->clear();
    }

private:
    QDialog dialog;
    Ui::Dialog ui;
};

int main(int argc, char** argv)
{
    QApplication app(argc, argv);

    QFileInfo jsFileInfo(QDir::currentPath() + "/qwebchannel.js");

    if (!jsFileInfo.exists())
        QFile::copy(":/qtwebchannel/qwebchannel.js",jsFileInfo.absoluteFilePath());

    // setup the QWebSocketServer
    QWebSocketServer server(QStringLiteral("QWebChannel Standalone Example Server"), QWebSocketServer::NonSecureMode);
    if (!server.listen(QHostAddress::LocalHost, 12345)) {
        qFatal("Failed to open web socket server.");
        return 1;
    }

    // wrap WebSocket clients in QWebChannelAbstractTransport objects
    WebSocketClientWrapper clientWrapper(&server);

    // setup the channel
    QWebChannel channel;
    QObject::connect(&clientWrapper, &WebSocketClientWrapper::clientConnected,
                     &channel, &QWebChannel::connectTo);

    // setup the dialog and publish it to the QWebChannel
    Dialog dialog;
    channel.registerObject(QStringLiteral("dialog"), &dialog);

    // open a browser window with the client HTML page
    QUrl url = QUrl::fromLocalFile(BUILD_DIR "/index.html");
    QDesktopServices::openUrl(url);

    dialog.displayMessage(QObject::tr("Initialization complete, opening browser at %1.").arg(url.toDisplayString()));

    return app.exec();
}

#include "main.moc"

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