[SOLVED] Help using SLOTs

  • I cannot for the life of me, get my slot to be connected/recognized. Any help would be appreciated.

    The following class just connects and polls a simple telnet server running on port 8090. The connection and reading work fine. (I was originally using UDP,hence the weird file/class names).

    @#ifndef XPUDP_H
    #define XPUDP_H

    #include <QtNetwork/QTcpSocket>

    class XpUDP : public QObject
    XpUDP(char * host = "localhost", int port = 8090);
    bool getIsConnected();
    QTcpSocket * getTelnet();
    bool connectTelnet();
    QTcpSocket * telnet;
    void initSocket();
    bool isConnected;
    char * myhost;
    int myport;
    private slots:
    void readPort();

    #endif // XPUDP_H

    @#include "xpudp.h"
    #include <iostream>
    #include <QtNetwork>

    XpUDP::XpUDP(char * host, int port)
    myhost = host;
    myport = port;

    void XpUDP::initSocket()
    telnet = new QTcpSocket;
    isConnected = connectTelnet();

    QTcpSocket * XpUDP::getTelnet() /* Just have this for testing purposes */
    return telnet;

    bool XpUDP::getIsConnected()
    return isConnected;

    void XpUDP::readPort() // This SLOT not being recognized
    int read_ret = 0;
    char buf[512];
    memset(buf, 0, 512);

    read_ret =  telnet->read(buf, 512);
    //printf("recived[%i] '%s'\n", read_ret, buf);
    std::cout << buf;
    memset(buf, 0, 512);


    bool XpUDP::connectTelnet()
    telnet->connectToHost(myhost, myport);
    if (telnet->waitForConnected(5000) == false)
    return false;
    connect(telnet, SIGNAL(readyRead()),
    this, SLOT(readPort())); /* I get QObject::connect: No such slot QObject::readPort() */
    return true;
    During runtime, if a connection is made I get this message in the console: QObject::connect: No such slot QObject::readPort(). Any help getting my slot reacting to the signal would be appreciated, or if events would be the way to go.

    I have Qt 4.8.2, using Qt Creator 2.4.1, qmake 2.01a, g++ 4.7.0, on a Linux Fedora 17 x86_64 system.

    FYI if it helps, I am making a moving map (MarbleMap) and instrument cluster for a flight sim.

    Thanks, Dave

  • You forgot to include the Q_OBJECT macro in your class declaration.

  • Moderators

    Be sure and add the Q_OBJECT macro when you define your class.

    [Edit: Andre beat me to it.]

  • Awesome, works now.

    After I added Q_OBJECT, did a make clean and rebuilt; I got an undefined reference to vtable for xxx. After running qmake -r all is good.

    Thanks, Dave

  • Moderators

    Be sure and edit your initial post to add [Solved] to the title. Thanks!

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