当前位置：首页 > article >正文

QT的错误记录:同文件的的两个QThread子类信号槽关联

article 2024/12/26 3:27:52

珍贵的记录

原本很简单的一个小测试代码，我原来把两个QThread子类放在一个文件里：结果报错

-1: error: ld.lld: error: undefined symbol: vtable for RecvThread

:-1: error: ld.lld: error: undefined symbol: vtable for SendThread

也没搞明白为什么，分开存放就OK了，先记录一下

一文不值的代码

RecvThread.h

#ifndef RECVTHREAD_H
#define RECVTHREAD_H
#include <QObject>
#include <QThread>
#include <QDebug>

class RecvThread : public QThread
{
    Q_OBJECT
public:
    void run() override {
        qDebug() << "RecvThread start";
        QThread::sleep(3);
        qDebug() << "RecvThread exit";
    }

public slots:
    void recv_msg(QString str) {
        qDebug() << "Setting string in OutputThread:" << str;
    }
};
#endif // RECVTHREAD_H

SendThread.h

#ifndef SENDTHREAD_H
#define SENDTHREAD_H
#include <QObject>
#include <QThread>
#include <QDebug>

class SendThread : public QThread
{
    Q_OBJECT
public:
    void run() override {
        qDebug() << "SendThread start";
        QString s("hello friend");
        emit send_msg(s);
        QThread::sleep(1);
        qDebug() << "SendThread exit";
    }
signals:
    void send_msg(QString str);
};
#endif // SENDTHREAD_H

main.cpp

#include <QApplication>
#include <QThread>
#include <QDebug>
#include <QString>
#include "SendThread.h"
#include "RecvThread.h"


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

    SendThread send_thread;
    RecvThread recv_thread;

    QObject::connect(&send_thread, SIGNAL(send_msg(QString)), &recv_thread, SLOT(recv_msg(QString)));
    qDebug() << "connect finish";
    emit send_thread.send_msg("hello one");

    send_thread.start();
    recv_thread.start();

    send_thread.wait();
    recv_thread.wait();

    return a.exec();
}

测试结果：