[SOLVED] what signal and slot for this server?

[kalster]

I am making a client/server program. in the server program, I need signal and slot for the following code to work correctly but i don't know what signal and slot to use. the ChatterBoxServer::incomingConnection function should be called from the chatterboxserver constructor when a connection has been made.

@ChatterBoxServer::ChatterBoxServer(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::ChatterBoxServer)
{
ui->setupUi(this);
QTcpServer *server = new QTcpServer();
bool success = server->listen(QHostAddress::Any, 4200);
if(!success)
{
ui->textEdit->append("Could not listen on port 4200.");
}

ui->textEdit->append("Ready");

}

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

void ChatterBoxServer::incomingConnection(int socketfd)
{
QTcpSocket *client = new QTcpSocket(this);
client->setSocketDescriptor(socketfd);
clients.insert(client);

ui->textEdit->append("New client from:"+ client->peerAddress().toString());

connect(client, SIGNAL(readyRead()), this, SLOT(readyRead()));
connect(client, SIGNAL(disconnected()), this, SLOT(disconnected()));
connect(client, SIGNAL(disconnected()), client, SLOT(deleteLater()));

}@

[Rahul Das]

"This":http://doc.qt.nokia.com/latest/qtcpserver.html#newConnection signal is emitted every time a new connection is available.

[kalster]

its not working for me. what i have is...
@connect(this, SIGNAL(newConnection()), this, SLOT(incomingConnection()));@

and i have tried...

@ connect(client, SIGNAL(newConnection()), this, SLOT(incomingConnection(int socketfd)));@

both do not work. what am i doing wrong?

@ChatterBoxServer::ChatterBoxServer(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::ChatterBoxServer)
{
ui->setupUi(this);
QTcpServer *server = new QTcpServer();
bool success = server->listen(QHostAddress::Any, 4200);
if(!success)
{
ui->textEdit->append("Could not listen on port 4200.");
}

ui->textEdit->append("Ready");
QTcpSocket *client = new QTcpSocket(this);
client->setSocketDescriptor(socketfd);
clients.insert(client);
emit newConnection();
connect(client, SIGNAL(newConnection()), this, SLOT(incomingConnection()));

}

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

void ChatterBoxServer::incomingConnection(int socketfd)
{
QTcpSocket *client = new QTcpSocket(this);
client->setSocketDescriptor(socketfd);
clients.insert(client);

ui->textEdit->append("New client from:"+ client->peerAddress().toString());

connect(client, SIGNAL(readyRead()), this, SLOT(readyRead()));
connect(client, SIGNAL(disconnected()), this, SLOT(disconnected()));
connect(client, SIGNAL(disconnected()), client, SLOT(deleteLater()));

}
@

[Rahul Das]

newConnection() is emitted by 'server'.

@connect(client, SIGNAL(newConnection()), this, SLOT(incomingConnection(int socketfd)));
@ is wrong. You can not pass value like this.

[kalster]

weil i have tried the following without the value and it still does not work.

@connect(client, SIGNAL(newConnection()), this, SLOT(incomingConnection()));@

[Rahul Das]

server is emitting the signal. So you may connect server to the slot :)

"This":http://thesmithfam.org/blog/2009/07/09/example-qt-chat-program/ could be useful as well.

[kalster]

i did not understand that sentence Rahul Das, the link you gave is the server program i am using. i am trying to make a ui form for the server instead of the console and i need a working signal for the function.

this is what i have in the main constructor and it not working.

@connect(client, SIGNAL(newConnection()), this, SLOT(incomingConnection()));@

[Rahul Das]

okay, so instead of cmd messages, you want a GUI for server. That is the change?

[kalster]

yes, but all i need is to get this signal to work and everything will be ok.

[Rahul Das]

I have made some changes in it like follows.

main
.......
@#include <QtGui/QApplication>
#include "mainwindow.h"

int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MainWindow w;
w.show();

return a.exec();

}
@

Ui contain just one label and Main window header and source.
.........................................................................
@#include <QMainWindow>
#include "server.h"

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
Q_OBJECT

public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
server * serverd;
private:
Ui::MainWindow *ui;

public slots:
void display1(QString);
};@

@#include "mainwindow.h"
#include "ui_mainwindow.h"

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

serverd = new server();
bool success = serverd->listen(QHostAddress::Any, 4200);

if(!success)
{
    return ;
}

connect(serverd,SIGNAL(display(QString)),this,SLOT(display1(QString)));

}

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

void MainWindow::display1(QString str)
{
ui->label->setText(str);
}@
......................................
Now our server daemon is here.
@#include <QStringList>
#include <QTcpServer>
#include <QTcpSocket>
#include <QMap>
#include <QSet>

class server : public QTcpServer
{
Q_OBJECT

public:
    server(QObject *parent=0);

private slots:
    void readyRead();
    void disconnected();
    void sendUserList();

protected:
    void incomingConnection(int socketfd);

private:
    QSet<QTcpSocket*> clients;
    QMap<QTcpSocket*,QString> users;

signals :
    void display(QString);@

@#include "server.h"

#include <QTcpSocket>
#include <QRegExp>

server::server(QObject *parent) : QTcpServer(parent)
{

}

void server::incomingConnection(int socketfd)
{
QTcpSocket *client = new QTcpSocket(this);
client->setSocketDescriptor(socketfd);
clients.insert(client);

qDebug() << "New client from:" << client->peerAddress().toString();

connect(client, SIGNAL(readyRead()), this, SLOT(readyRead()));
connect(client, SIGNAL(disconnected()), this, SLOT(disconnected()));

}

void server::readyRead()
{
QTcpSocket client = (QTcpSocket)sender();
while(client->canReadLine())
{
QString line = QString::fromUtf8(client->readLine()).trimmed();
qDebug() << "Read line:" << line;

    QRegExp meRegex("^/me:(.*)$");

    if(meRegex.indexIn(line) != -1)
    {
        QString user = meRegex.cap(1);
        users[client] = user;
        foreach(QTcpSocket *client, clients)
            client->write(QString("Server:" + user + " has joined.\n").toUtf8());
        sendUserList();
    }
    else if(users.contains(client))
    {
        QString message = line;
        QString user = users[client];
        qDebug() << "User:" << user;
        qDebug() << "Message:" << message;

        foreach(QTcpSocket *otherClient, clients)
            otherClient->write(QString(user + ":" + message + "\n").toUtf8());
    }
    else
    {
        qWarning() << "Got bad message from client:" << client->peerAddress().toString() << line;
    }
}

}

void server::disconnected()
{
QTcpSocket client = (QTcpSocket)sender();
qDebug() << "Client disconnected:" << client->peerAddress().toString();

clients.remove(client);

QString user = users[client];
users.remove(client);

sendUserList();
foreach(QTcpSocket *client, clients)
    client->write(QString("Server:" + user + " has left.\n").toUtf8());

}

void server::sendUserList()
{
QStringList userList;
foreach(QString user, users.values())
userList << user;

foreach(QTcpSocket *client, clients)
    client->write(QString("/users:" + userList.join(",") + "\n").toUtf8());
emit display(QString("/users:" + userList.join(",") + "\n").toUtf8());

}@

As you can see, what is done here is, whenever there is something to be displayed, signal is emitted. Mainwindow catches that and displays!

use @emit display("Your string")@ whenever you want to display. (change client->write to emit disp...)

[kalster]

the code works excellent. thank you :)