QThread(moveToThread)

MainWindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include "MyThread.h"
#include <QThread>

QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

private:
    Ui::MainWindow *ui;
private:
    MyThread *myObject;
    QThread *newThread;

private slots:
    void SlotNum(QString num);
};
#endif // MAINWINDOW_H

MainWindow.cpp

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

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    newThread = new QThread;
    myObject = new MyThread;
    myObject->moveToThread(newThread);            //创建线程
    connect(newThread, &QThread::started ,myObject, &MyThread::display);

    connect(myObject, &MyThread::SiganlNum, this, &MainWindow::SlotNum);

    connect(ui->pushButton_open, &QPushButton::clicked, this, [=]
    {
        newThread->start();
        myObject->filenameList(10);
        myObject->stopwork(false);//开始
    });
    connect(ui->pushButton_over, &QPushButton::clicked, this, [=]
    {
        myObject->stopwork(true);//停止
        newThread->quit();
        newThread->wait();               //等待线程退出
    });
}

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

void MainWindow::SlotNum(QString num)
{
    ui->lcdNumber->display(num);
}

MyThread.h

#ifndef MYTHREAD_H
#define MYTHREAD_H

#include <QObject>
#include <QFileInfo>
class MyThread : public QObject
{
    Q_OBJECT
public:
    explicit MyThread(QObject *parent = nullptr);

public slots:
    void display();
    void stopwork(bool stop);
public:
    void filenameList(const int &ss);

signals:
    void SiganlNum(QString num);

private:
    bool m_stop_;
    int num;
};

#endif // MYTHREAD_H

MyThread.cpp

#include "MyThread.h"
#include <QDebug>
#include <QThread>
MyThread::MyThread(QObject *parent) : QObject(parent)
{
    m_stop_ = false;
    num = 0;
}


void MyThread::display()
{
    int i = 0;
    while(1)
    {
        if(m_stop_)
        {
            break;
        }
        qDebug() << "i is" << num;
        num++;
        emit SiganlNum(QString::number(num));
        QThread::sleep(1);
    }
}


void MyThread::stopwork(bool stop)
{
    m_stop_ = stop;
}

void MyThread::filenameList(const int &ss)
{
    num = ss;
}