Broadcast string with udpsocket

[wirasto]

I'm try broadcast string with udpsocket. But not work


Server Source Code

sender.cpp

#include "sender.h"
 
Sender::Sender()
{
    socket=new QUdpSocket(this);
    QTimer *timer=new QTimer(this);
    timer->setInterval(100);
    timer->start();
 
    connect(timer, SIGNAL(timeout()), this, SLOT(siarkan()));
}
 
void Sender::siarkan()
{
    QByteArray datagram;
    QDataStream out(&datagram, QIODevice::WriteOnly);
    out.setVersion(QDataStream::Qt_4_0);
    out << "Salawaku" << "Wirasto" << "Slackware";
 
    socket->writeDatagram(datagram, QHostAddress::Broadcast, 9988);
}

#include "sender.h"

Sender::Sender()
{
    socket=new QUdpSocket(this);
    QTimer *timer=new QTimer(this);
    timer->setInterval(100);
    timer->start();

    connect(timer, SIGNAL(timeout()), this, SLOT(siarkan()));
}

void Sender::siarkan()
{
    QByteArray datagram;
    QDataStream out(&datagram, QIODevice::WriteOnly);
    out.setVersion(QDataStream::Qt_4_0);
    out << "Salawaku" << "Wirasto" << "Slackware";

    socket->writeDatagram(datagram, QHostAddress::Broadcast, 9988);
}

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main.cpp

#include <QtCore/QCoreApplication>
#include "sender.h"
 
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
 
    Sender send;
 
    return a.exec();
}

#include <QtCore/QCoreApplication>
#include "sender.h"

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    Sender send;

    return a.exec();
}

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Client Source Code

dialog.cpp

#include "dialog.h"
#include "ui_dialog.h"
#include <QDebug>
 
Dialog::Dialog(QWidget *parent)
    : QDialog(parent), ui(new Ui::Dialog)
{
    ui->setupUi(this);
 
    socket=new QUdpSocket(this);
    socket->bind(9988);
 
    connect(socket, SIGNAL(readyRead()), this, SLOT(terimaData()));
}
 
Dialog::~Dialog()
{
    delete ui;
}
 
void Dialog::terimaData()
{
    QString group, nama, distro;
 
 
    while( socket->hasPendingDatagrams() )
    {
        QByteArray buffer( socket->pendingDatagramSize(), 0 );
        socket->readDatagram( buffer.data(), buffer.size() );
        QDataStream stream( buffer );
        stream.setVersion( QDataStream::Qt_4_0 );
        stream >> group >> nama >> distro;
    }
 
    ui->lineEdit->setText(group);
    ui->lineEdit_2->setText(nama);
    ui->lineEdit_3->setText(distro);
}

#include "dialog.h"
#include "ui_dialog.h"
#include <QDebug>

Dialog::Dialog(QWidget *parent)
    : QDialog(parent), ui(new Ui::Dialog)
{
    ui->setupUi(this);

    socket=new QUdpSocket(this);
    socket->bind(9988);

    connect(socket, SIGNAL(readyRead()), this, SLOT(terimaData()));
}

Dialog::~Dialog()
{
    delete ui;
}

void Dialog::terimaData()
{
    QString group, nama, distro;


    while( socket->hasPendingDatagrams() )
    {
        QByteArray buffer( socket->pendingDatagramSize(), 0 );
        socket->readDatagram( buffer.data(), buffer.size() );
        QDataStream stream( buffer );
        stream.setVersion( QDataStream::Qt_4_0 );
        stream >> group >> nama >> distro;
    }

    ui->lineEdit->setText(group);
    ui->lineEdit_2->setText(nama);
    ui->lineEdit_3->setText(distro);
}

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main.cpp

#include <QtGui/QApplication>
#include "dialog.h"
 
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Dialog w;
    w.show();
    return a.exec();
}

#include <QtGui/QApplication>
#include "dialog.h"

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Dialog w;
    w.show();
    return a.exec();
}

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What's wrong with my code ?

[kwisp]

Is "readyRead()" emitting?

[wirasto]

Is readyRead signal not emitting in my source code ?

How and where I must emit readyRead signal ?

[kwisp]

>where I must emit readyRead signal ?
nowhere. Qt makes it.

you can write:

void Dialog::terimaData()
{
qDebug()<<__PRETTY_FUNCTION__;
    QString group, nama, distro;
...

void Dialog::terimaData()
{
qDebug()<<__PRETTY_FUNCTION__;
    QString group, nama, distro;
...

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and see log.

[wirasto]

void Dialog::terimaData()
{
    i++;
    qDebug() << QString("It's OK %1").arg(i);
    .....

void Dialog::terimaData()
{
    i++;
    qDebug() << QString("It's OK %1").arg(i);
    .....

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Result :

It's OK 1
It's OK 2
It's OK 3
It's OK 4
........
........


I think readyRead() is emitting...

So, why I still can't catch string broadcasting ?

[kwisp]

try to use another function to read data
as:
QByteArray QIODevice::readAll ()
qint64 QIODevice::readLine ( char * data, qint64 maxSize )
etc.
I think that the problem is QDataStream or QByteArray usage.