调用另一个线程的方法

QThread - Call a method of another thread

本文关键字:方法 线程 另一个 调用      更新时间:2023-10-16

我试图调用另一个线程(不是Main)的方法,使用invokeMethod。不幸的是,这会使应用程序在尝试执行invokeMethod时立即崩溃!

我搞错什么了吗?

//main.cpp

#include <QtCore>
#include "entrypointclass.h"
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    qDebug() << a.thread()->currentThreadId() << " - Application started.";
    EntryPointClass entryPoint;
    entryPoint.runInNewThread();
    return a.exec();
}
//Entrypoint.h

#ifndef ENTRYPOINTCLASS_H
#define ENTRYPOINTCLASS_H
#include "worker.h"
#include <QtCore>
class EntryPointClass : public QObject
{
    Q_OBJECT
public:
    EntryPointClass();
    ~EntryPointClass();
    void runInNewThread();
public slots:
    void timeoutExpired();
private:
    Worker* m_Worker;
    QThread* m_Thread;
};
#endif // ENTRYPOINTCLASS_H
//Entrypoint.cpp

#include <QTCore>
#include "entrypointclass.h"
#include "Worker.h"
EntryPointClass::EntryPointClass()
{
    qDebug() << "EntryPointClass created";

}
EntryPointClass::~EntryPointClass()
{
    qDebug() << "EntryPointClass destroyed";
}
void EntryPointClass::runInNewThread()
{
    QThread* m_Thread = new QThread;
    Worker* m_Worker = new Worker();

    connect(m_Thread, SIGNAL(started()), m_Worker, SLOT(doSomething()));
    connect(m_Worker, SIGNAL(finished()), m_Thread, SLOT(quit()));
    connect(m_Thread, SIGNAL(finished()), m_Thread, SLOT(deleteLater()));
    connect(m_Thread, SIGNAL(finished()), m_Worker, SLOT(deleteLater()));
    QTimer* timer = new QTimer;
    timer->setSingleShot(true);
    //bool bOK = connect(timer, SIGNAL(timeout()), m_Worker, SLOT(closeWorker()), Qt::BlockingQueuedConnection);
    connect(timer, SIGNAL(timeout()), this, SLOT(timeoutExpired()));
    m_Worker->moveToThread(m_Thread);
    m_Thread->start();
    timer->start(5000);
}
void EntryPointClass::timeoutExpired()
{
    qDebug() << "timeout expired";
    if (m_Worker != NULL)
    {
        QMetaObject::invokeMethod(m_Worker, "closeWorker", Qt::QueuedConnection);
    }
}
//Worker.h

#ifndef WORKER_H
#define WORKER_H
#include <QtCore>
class Worker : public QObject
{
    Q_OBJECT
public:
    Worker();
    ~Worker();
public slots:
    void doSomething();
    void closeWorker();
private:
    bool m_bAbort;
    QMutex m_mutex;

signals:
    void finished();
};
#endif // WORKER_H
//Worker.cpp

#include "worker.h"
#include <unistd.h>
#include "QTcore"
Worker::Worker()
    : m_mutex()
{
    qDebug() << this->thread()->currentThreadId() << "Worker created";
    m_bAbort = false;
    //qDebug() << QString("Thread %1 - Worker created").arg("");//this->thread()->currentThreadId());
}
Worker::~Worker()
{
    qDebug() << this->thread()->currentThreadId() << "Worker destroyed";
}
void Worker::doSomething()
{
    while(!m_bAbort)
    {
        sleep(2);
        qDebug() << this->thread()->currentThreadId() << "Do Something!";
    }
    emit finished();
}
void Worker::closeWorker()
{
    qDebug() << this->thread()->currentThreadId() << "closeWorker triggered!";
    QMutexLocker mutexLocker(&m_mutex);
    m_bAbort = true;
}

不要直接调用方法,而是尝试发布一个自定义事件。这将要求您在处理自定义事件的目标上实现一个事件过滤器。只要目标线程中的事件循环处于活动状态,事件发布总是有效的。

看看这里的答案。也在这里。