receiver.cpp Example File

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  #include <QtWidgets>
  #include <QtNetwork>

  #include "receiver.h"

  Receiver::Receiver(QWidget *parent)
      : QWidget(parent)
  {
      statusLabel = new QLabel(tr("Listening for broadcasted messages"));
      statusLabel->setWordWrap(true);

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

      udpSocket = new QUdpSocket(this);
      udpSocket->bind(45454, QUdpSocket::ShareAddress);

      connect(udpSocket, SIGNAL(readyRead()),
              this, SLOT(processPendingDatagrams()));
      connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));

      QHBoxLayout *buttonLayout = new QHBoxLayout;
      buttonLayout->addStretch(1);
      buttonLayout->addWidget(quitButton);
      buttonLayout->addStretch(1);

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

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

  void Receiver::processPendingDatagrams()
  {
      while (udpSocket->hasPendingDatagrams()) {
          QByteArray datagram;
          datagram.resize(udpSocket->pendingDatagramSize());
          udpSocket->readDatagram(datagram.data(), datagram.size());
          statusLabel->setText(tr("Received datagram: \"%1\"")
                               .arg(datagram.data()));
      }
  }