Qt Reference Documentation

sender.cpp Example File

network/broadcastsender/sender.cpp
 /****************************************************************************
 **
 ** Copyright (C) 2015 The Qt Company Ltd.
 ** Contact: http://www.qt.io/licensing/
 **
 ** This file is part of the examples of the Qt Toolkit.
 **
 ** $QT_BEGIN_LICENSE:BSD$
 ** You may use this file under the terms of the BSD license as follows:
 **
 ** "Redistribution and use in source and binary forms, with or without
 ** modification, are permitted provided that the following conditions are
 ** met:
 **   * Redistributions of source code must retain the above copyright
 **     notice, this list of conditions and the following disclaimer.
 **   * Redistributions in binary form must reproduce the above copyright
 **     notice, this list of conditions and the following disclaimer in
 **     the documentation and/or other materials provided with the
 **     distribution.
 **   * Neither the name of The Qt Company Ltd nor the names of its
 **     contributors may be used to endorse or promote products derived
 **     from this software without specific prior written permission.
 **
 **
 ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
 **
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/

 #include <QtGui>
 #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;
 }