- Qt 5.5
- Qt QML
- C++ Extensions: Network Access Manager Factory Example
- main.cpp Example File
- Qt 5.5.1 Reference Documentation

# main.cpp Example File

networkaccessmanagerfactory/main.cpp

    /****************************************************************************
    **
    ** Copyright (C) 2015 The Qt Company Ltd.
    ** Contact: http://www.qt.io/licensing/
    **
    ** This file is part of the demonstration applications of the Qt Toolkit.
    **
    ** $QT_BEGIN_LICENSE:BSD$
    ** You may use this file under the terms of the BSD license as follows:
    **
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    ** modification, are permitted provided that the following conditions are
    ** met:
    **   * Redistributions of source code must retain the above copyright
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    **     distribution.
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    **     contributors may be used to endorse or promote products derived
    **     from this software without specific prior written permission.
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    #include <QCommandLineParser>
    #include <QGuiApplication>
    #include <QNetworkAccessManager>
    #include <QNetworkProxy>

    #include <QQmlEngine>
    #include <QQmlNetworkAccessManagerFactory>
    #include <QtQuick/QQuickView>

    /*
       This example illustrates using a QQmlNetworkAccessManagerFactory to
       create a QNetworkAccessManager with a proxy.

       Usage:
         networkaccessmanagerfactory [-host <proxy> -port <port>] [file]
    */

    #ifndef QT_NO_NETWORKPROXY
    static QString proxyHost;
    static int proxyPort = 0;
    #endif // !QT_NO_NETWORKPROXY

    class MyNetworkAccessManagerFactory : public QQmlNetworkAccessManagerFactory
    {
    public:
        virtual QNetworkAccessManager *create(QObject *parent);
    };

    QNetworkAccessManager *MyNetworkAccessManagerFactory::create(QObject *parent)
    {
        QNetworkAccessManager *nam = new QNetworkAccessManager(parent);
    #ifndef QT_NO_NETWORKPROXY
        if (!proxyHost.isEmpty()) {
            qDebug() << "Created QNetworkAccessManager using proxy" << (proxyHost + ":" + QString::number(proxyPort));
            QNetworkProxy proxy(QNetworkProxy::HttpCachingProxy, proxyHost, proxyPort);
            nam->setProxy(proxy);
        }
    #endif // !QT_NO_NETWORKPROXY

        return nam;
    }

    int main(int argc, char ** argv)
    {
        QUrl source("qrc:view.qml");

        QGuiApplication app(argc, argv);

        QCommandLineParser parser;
    #ifndef QT_NO_NETWORKPROXY
        QCommandLineOption proxyHostOption("host", "The proxy host to use.", "host");
        parser.addOption(proxyHostOption);
        QCommandLineOption proxyPortOption("port", "The proxy port to use.", "port", "0");
        parser.addOption(proxyPortOption);
    #endif // !QT_NO_NETWORKPROXY
        parser.addPositionalArgument("file", "The file to use.");
        QCommandLineOption helpOption = parser.addHelpOption();
        parser.setSingleDashWordOptionMode(QCommandLineParser::ParseAsLongOptions);
        QStringList arguments = QCoreApplication::arguments();
        if (!parser.parse(arguments)) {
            qWarning() << parser.helpText() << '\n' << parser.errorText();
            exit(1);
        }
        if (parser.isSet(helpOption)) {
            qWarning() << parser.helpText();
            exit(0);
        }
    #ifndef QT_NO_NETWORKPROXY
        if (parser.isSet(proxyHostOption))
            proxyHost = parser.value(proxyHostOption);
        if (parser.isSet(proxyPortOption)) {
            bool ok = true;
            proxyPort = parser.value(proxyPortOption).toInt(&ok);
            if (!ok || proxyPort < 1 || proxyPort > 65535) {
                qWarning() << parser.helpText() << "\nNo valid port given. It should\
                              be a number between 1 and 65535";
                exit(1);
            }
        }
    #endif // !QT_NO_NETWORKPROXY
        if (parser.positionalArguments().count() == 1)
            source = QUrl::fromLocalFile(parser.positionalArguments().first());

        QQuickView view;
        view.engine()->setNetworkAccessManagerFactory(new MyNetworkAccessManagerFactory);

        view.setSource(source);
        view.show();

        return app.exec();
    }