- Qt 5.5
- Qt Network
- Broadcast Sender Example
- sender.cpp Example File
- Qt 5.5.1 Reference Documentation

# sender.cpp Example File

broadcastsender/sender.cpp

    /****************************************************************************
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    ** This file is part of the examples of the Qt Toolkit.
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    #include <QtWidgets>
    #include <QtNetwork>

    #include "sender.h"

    Sender::Sender(QWidget *parent)
        : QWidget(parent)
    {
        statusLabel = new QLabel(tr("Ready to broadcast datagrams on port 45454"));
        statusLabel->setWordWrap(true);

        startButton = new QPushButton(tr("&Start"));
        quitButton = new QPushButton(tr("&Quit"));

        buttonBox = new QDialogButtonBox;
        buttonBox->addButton(startButton, QDialogButtonBox::ActionRole);
        buttonBox->addButton(quitButton, QDialogButtonBox::RejectRole);

        timer = new QTimer(this);
        udpSocket = new QUdpSocket(this);
        messageNo = 1;

        connect(startButton, SIGNAL(clicked()), this, SLOT(startBroadcasting()));
        connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));
        connect(timer, SIGNAL(timeout()), this, SLOT(broadcastDatagram()));

        QVBoxLayout *mainLayout = new QVBoxLayout;
        mainLayout->addWidget(statusLabel);
        mainLayout->addWidget(buttonBox);
        setLayout(mainLayout);

        setWindowTitle(tr("Broadcast Sender"));
    }

    void Sender::startBroadcasting()
    {
        startButton->setEnabled(false);
        timer->start(1000);
    }

    void Sender::broadcastDatagram()
    {
        statusLabel->setText(tr("Now broadcasting datagram %1").arg(messageNo));
        QByteArray datagram = "Broadcast message " + QByteArray::number(messageNo);
        udpSocket->writeDatagram(datagram.data(), datagram.size(),
                                 QHostAddress::Broadcast, 45454);
        ++messageNo;
    }