sender.cpp 范例文件

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#include <QtWidgets>
#include <QtNetwork>
#include "sender.h"
Sender::Sender(QWidget *parent)
    : QDialog(parent)
{
    groupAddress = QHostAddress("239.255.43.21");
    statusLabel = new QLabel(tr("Ready to multicast datagrams to group %1 on port 45454").arg(groupAddress.toString()));
    ttlLabel = new QLabel(tr("TTL for multicast datagrams:"));
    ttlSpinBox = new QSpinBox;
    ttlSpinBox->setRange(0, 255);
    QHBoxLayout *ttlLayout = new QHBoxLayout;
    ttlLayout->addWidget(ttlLabel);
    ttlLayout->addWidget(ttlSpinBox);
    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(ttlSpinBox, SIGNAL(valueChanged(int)), this, SLOT(ttlChanged(int)));
    connect(startButton, SIGNAL(clicked()), this, SLOT(startSending()));
    connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));
    connect(timer, SIGNAL(timeout()), this, SLOT(sendDatagram()));
    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(statusLabel);
    mainLayout->addLayout(ttlLayout);
    mainLayout->addWidget(buttonBox);
    setLayout(mainLayout);
    setWindowTitle(tr("Multicast Sender"));
    ttlSpinBox->setValue(1);
}
void Sender::ttlChanged(int newTtl)
{
    udpSocket->setSocketOption(QAbstractSocket::MulticastTtlOption, newTtl);
}
void Sender::startSending()
{
    startButton->setEnabled(false);
    timer->start(1000);
}
void Sender::sendDatagram()
{
    statusLabel->setText(tr("Now sending datagram %1").arg(messageNo));
    QByteArray datagram = "Multicast message " + QByteArray::number(messageNo);
    udpSocket->writeDatagram(datagram.data(), datagram.size(),
                             groupAddress, 45454);
    ++messageNo;
}