#ifndef MYTHREAD_H

 #define MYTHREAD_H

 #include <QThread>

 class myThread : public QObject

 {

     Q_OBJECT

 public:

     explicit myThread(QObject *parent = );

     //线程处理函数

     void myTimeout();

     void setFlag(bool flag = true);

 signals:

     void mySignal();

 public slots:

 private:

     bool isStop;

 };

 #endif // MYTHREAD_H

 #include "mythread.h"

 #include <QThread>

 #include <QDebug>

 myThread::myThread(QObject *parent) : QObject(parent)

 {

     isStop = false;

 }

 void myThread::myTimeout()

 {

     while( !isStop )

     {

         QThread::sleep();

         emit mySignal();

          qDebug() << "子线程号：" << QThread::currentThread();

          if(isStop)

          {

              break;

          }

     }

 }

 void myThread::setFlag(bool flag)

 {

     isStop = flag;

 }

 #ifndef WIDGET_H

 #define WIDGET_H

 #include "mythread.h"

 #include <QWidget>

 #include <QTimer>

 #include <QThread>

 #include <QDebug>

 namespace Ui {

 class Widget;

 }

 class Widget : public QWidget

 {

     Q_OBJECT

 public:

     explicit Widget(QWidget *parent = );

     ~Widget();

     void dealSignal();

     void dealClose();

 signals:

     void startThread(); //启动子线程的信号

 private slots:

     void on_start_clicked();

     void on_stop_clicked();

 private:

     Ui::Widget *ui;

     myThread *myT;

     QThread *thread;

 };

 #endif // WIDGET_H

 #include "widget.h"

 #include "ui_widget.h"

 #include "mythread.h"

 Widget::Widget(QWidget *parent) :

     QWidget(parent),

     ui(new Ui::Widget)

 {

     ui->setupUi(this);

     myT = new myThread;//不能初始化指定父类myThread(this)

     //创建子线程

     thread = new QThread(this);

     //把自定义线程加入到子线程中

     myT->moveToThread(thread);

     connect(myT, &myThread::mySignal, this, &Widget::dealSignal);

     qDebug() << "主线程号：" << QThread::currentThread();

     connect(this, &Widget::startThread, myT, &myThread::myTimeout);

     //窗口关闭时调用线程关闭，前提是线程要运行完当前任务

     connect(this, &Widget::destroyed, this, &Widget::dealClose);

 }

 Widget::~Widget()

 {

     delete ui;

 }

 void Widget::dealClose()

 {

     on_stop_clicked();

     delete myT;

 }

 void Widget::dealSignal()

 {

     static int i = ;

     i++;

     ui->lcdNumber->display(i);

 }

 void Widget::on_start_clicked()

 {

     if(thread->isRunning() == true)

     {

         return;

     }

     //启动线程，但是没有启动线程处理函数

     thread->start();

     myT->setFlag(false);

     //不能直接调用线程处理函数，

     //直接调用，导致，线程处理函数和主线程是在同一个线程

     //只能通过 signal - slot 方式调用

     emit startThread();

 }

 void Widget::on_stop_clicked()

 {

     if(thread->isRunning() == false)

     {

         return;

     }

     myT->setFlag(true);

     thread->quit();

     thread->wait();

 }