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Qt线程有两种方法：1是继承qthread； 2就是MovetoThread方法；

目的：

第二种方法有其独特的用法，就是可以做成任务槽的方式，做完任务就返回，然后exec进入事件循环，可以避免单一任务频繁创建线程的开销，又可以达到在另一个线程中进行任务的执行；

问题：

在线程中，我想使用个定时器，然后通过点击主线程的按钮来通知此线程的定时器开启和停止；发现会出现”无法关闭在另一个线程的定时器”的提示

解决办法：

无法关闭在另一个线程的定时器，是因为定时器要在新的线程中new,不要在构造函数中new出来，这样定时器才属于另一个线程，而不是创造该线程的主线程中；

以下是项目代码：

Worker.h

#pragma once

#include <QObject>
class QTimer;

class Worker : public QObject
{
    Q_OBJECT
public:
    explicit Worker(QObject *parent = nullptr);
    ~Worker();

public slots:
    void WorkerTaskStartSlot(void);
    void TaskFinished(void);
private slots:
    void TimerOutToDoSomethingSlot(void);
signals:
    void WorkertResultSig(void);

private:
    QTimer *m_pTimer = nullptr;
};

Worker.cpp

#include "Worker.h"
#include <QDebug>
#include <QThread>
#include <QTimer>

Worker::Worker(QObject *parent) : QObject(parent)
{
    qDebug()<<__FUNCTION__<<"threadid"<< QThread::currentThreadId();

}

Worker::~Worker()
{
    TaskFinished();
      qDebug()<<__FUNCTION__<<"threadid"<< QThread::currentThreadId();
}


void Worker::WorkerTaskStartSlot(void)
{
    qDebug()<<__FUNCTION__<<"threadid"<< QThread::currentThreadId();
    emit WorkertResultSig();

    m_pTimer = new QTimer(this);
    connect(m_pTimer,&QTimer::timeout,this,&Worker::TimerOutToDoSomethingSlot);
    m_pTimer->start(1000);
}


void Worker::TaskFinished(void)
{
    qDebug()<<__FUNCTION__<<"threadid"<< QThread::currentThreadId();

    if(m_pTimer)
    {
        if(m_pTimer->isActive())
        {
            m_pTimer->stop();
            qDebug()<<__FUNCTION__<<"stop timer"<< QThread::currentThreadId();
        }

        delete m_pTimer;
        m_pTimer = nullptr;
    }
}


void Worker::TimerOutToDoSomethingSlot(void)
{
    qDebug()<<__FUNCTION__<<"threadid"<< QThread::currentThreadId();
}

MainWindow.h

#pragma once

#include <QMainWindow>
class QPushButton;
class QWidget;
class Worker;
class QThread;

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();
private:
    void InitCtrl(void);
private slots:
    void StartTaskBtnSlot(const bool &checked);
    void WorkertResultSlot(void);
private:
    QPushButton *m_pStartTaskBtn = nullptr;
    QWidget *m_pCenterWidget = nullptr;
    Worker *m_pWorker = nullptr;
    QThread *m_pWorkerThread = nullptr;
};

MainWindow.cpp

#include "MainWindow.h"
#include <QVBoxLayout>
#include <QPushButton>
#include <QWidget>
#include <QDebug>
#include <QThread>
#include "Worker.h"

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    InitCtrl();
    qDebug()<<__FUNCTION__<<"mainwindow thread id"<< QThread::currentThreadId();
}

MainWindow::~MainWindow()
{
    if(m_pStartTaskBtn->isChecked())
    {
        m_pStartTaskBtn->click();
    }
}

void MainWindow::InitCtrl(void)
{
    m_pCenterWidget = new QWidget(this);
    m_pStartTaskBtn = new QPushButton(QStringLiteral("Start"),this);

    QVBoxLayout *pvertlayout = new QVBoxLayout();
    pvertlayout->addWidget(m_pStartTaskBtn);
    m_pCenterWidget->setLayout(pvertlayout);

    setCentralWidget(m_pCenterWidget);

    m_pStartTaskBtn->setCheckable(true);
    connect(m_pStartTaskBtn,&QPushButton::clicked,this,&MainWindow::StartTaskBtnSlot);

}

void MainWindow::StartTaskBtnSlot(const bool &checked)
{
    if(checked)
    {
        m_pStartTaskBtn->setText(QStringLiteral("Close"));

        m_pWorkerThread = new QThread();
        m_pWorker = new Worker();

        // move the task object to the thread BEFORE connecting any signal/slots
        m_pWorker->moveToThread(m_pWorkerThread);

        connect(m_pWorkerThread, SIGNAL(started()), m_pWorker, SLOT(WorkerTaskStartSlot()));
        connect(m_pWorker, SIGNAL(WorkertResultSig()), this, SLOT(WorkertResultSlot()));

        // automatically delete thread and task object when work is done:
        connect(m_pWorkerThread, SIGNAL(finished()), m_pWorker, SLOT(deleteLater()));
        connect(m_pWorkerThread, SIGNAL(finished()), m_pWorkerThread, SLOT(deleteLater()));


        m_pWorkerThread->start();
    }
    else
    {
        m_pStartTaskBtn->setText(QStringLiteral("Start"));
        m_pWorkerThread->quit();
        m_pWorkerThread->wait();
    }
}

void MainWindow::WorkertResultSlot(void)
{
    qDebug()<<__FUNCTION__<<"threadid"<<QThread::currentThreadId();

}

结果：

MainWindow::MainWindow mainwindow thread id 0x2bf0
Worker::Worker threadid 0x2bf0
Worker::WorkerTaskStartSlot threadid 0x4af0
MainWindow::WorkertResultSlot threadid 0x2bf0
Worker::TimerOutToDoSomethingSlot threadid 0x4af0
Worker::TimerOutToDoSomethingSlot threadid 0x4af0
Worker::TimerOutToDoSomethingSlot threadid 0x4af0
Worker::TimerOutToDoSomethingSlot threadid 0x4af0
Worker::TaskFinished threadid 0x4af0
Worker::TaskFinished stop timer 0x4af0
Worker::~Worker threadid 0x4af0

项目源码下载地址：

Qt的MoveToThread显示无法关闭在另一个线程的定时器-C++文档类资源-CSDN下载