main.cpp Example File | Qt WebChannel 5.6

Qt 5.6 | Qt WebChannel | Qt WebChannel Standalone Example | main.cpp Example File

Qt 5.6.2 Reference Documentation

# main.cpp Example File

standalone/main.cpp

      /****************************************************************************
      **
      ** Copyright (C) 2014 Klar��lvdalens 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.
      **
      ** $QT_BEGIN_LICENSE:LGPL21$
      ** Commercial License Usage
      ** Licensees holding valid commercial Qt licenses may use this file in
      ** 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
      ** and conditions see http://www.qt.io/terms-conditions. For further
      ** 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
      ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
      **
      ** $QT_END_LICENSE$
      **
      ****************************************************************************/

      #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"