Qt 5.6 | Qt Network | Broadcast Sender Example | sender.cpp Example File

Qt 5.6.2 Reference Documentation

# sender.cpp Example File

broadcastsender/sender.cpp

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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;
      }