Receiver.cpp Example File

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    #include "Receiver.hpp"

    #include <QtNetwork/QUdpSocket>

    Receiver::Receiver(QObject *parent)
        : QObject(parent)
    {
        // Initialize the multicast address
        m_groupAddress = QHostAddress("239.255.43.21");

        /**
         * Initialize the 'status' property with some data, it will
         * be shown in the UI until the first datagram arrives.
         */
        m_status = tr("Listening for multicasted messages");

        // Create a new UDP socket and bind it against port 45454
        m_udpSocket = new QUdpSocket(this);
        m_udpSocket->bind(45454, QUdpSocket::ShareAddress);

        // Tell the UDP socket which multicast group it should join
        m_udpSocket->joinMulticastGroup(m_groupAddress);

        /**
         * Create signal/slot connection to invoke processPendingDatagrams() whenever
         * a new multicast datagram is received by the socket.
         */
        connect(m_udpSocket, SIGNAL(readyRead()), this, SLOT(processPendingDatagrams()));
    }

    void Receiver::processPendingDatagrams()
    {
        // Now read all available datagrams from the socket
        while (m_udpSocket->hasPendingDatagrams()) {
            // Create a temporary buffer ...
            QByteArray datagram;

            // ... with the size of the received multicast datagram ...
            datagram.resize(m_udpSocket->pendingDatagramSize());

            // ... and copy over the received multicast datagram into that buffer.
            m_udpSocket->readDatagram(datagram.data(), datagram.size());

            // Update the 'status' property with the content of the received multicast datagram
            m_status = tr("Received datagram: \"%1\"").arg(datagram.data());
            emit statusChanged();
        }
    }

    QString Receiver::status() const
    {
        return m_status;
    }