sender.cpp Example File

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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;
  }