Qt Reference Documentation

receiver.cpp Example File

network/broadcastreceiver/receiver.cpp
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 #include <QtGui>
 #include <QtNetwork>

 #include "receiver.h"

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

 #ifdef Q_OS_SYMBIAN
     quitAction = new QAction(tr("Exit"), this);
     quitAction->setSoftKeyRole(QAction::NegativeSoftKey);
     addAction(quitAction);
 #else
     quitButton = new QPushButton(tr("&Quit"));
 #endif

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

     connect(udpSocket, SIGNAL(readyRead()),
             this, SLOT(processPendingDatagrams()));
 #ifdef Q_OS_SYMBIAN
     connect(quitAction, SIGNAL(triggered()), this, SLOT(close()));

     QVBoxLayout *mainLayout = new QVBoxLayout;
     mainLayout->addWidget(statusLabel);
     setLayout(mainLayout);
 #else
     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);
 #endif

     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()));
     }
 }