创建一个类继承自QRunnable：

class Thread02 : public QRunnable

重写run方法：

void run() override;

在main函数里面加入线程池：

Thread02 *th = new Thread02();QThreadPool::globalInstance()->start(th);

#include <QtCore/QCoreApplication>
#include <iostream>
#include "Thread01.h"
#include "Thread02.h"
#include <QThreadPool>

using namespace std;

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    cout << "main thread" << QThread::currentThreadId() << endl;

    /*Thread01 th;
    th.start();*/

    Thread02 *th = new Thread02();
    QThreadPool::globalInstance()->start(th);

    cout << "main thread end" << endl;
    return a.exec();
}