QThread跟随父对象自动退出

QThread自动退出

1. 通过继承QThread类，重写 void run() 函数；
2. 将耗时操作放入run函数，在子线程中执行；
3. 设置Worker实例父对象；
4. 父对象退出后，Worker实例析构，子线程自动退出；

实现代码

Worker.h

#ifndef WORKER_H
#define WORKER_H

#include <QThread>

class Worker : public QThread
{
    Q_OBJECT

public:
    explicit Worker(QObject *parent = nullptr);

    ~Worker();

    void run();

};

#endif // WORKER_H

Worker.cpp

#include "worker.h"
#include <QtCore>

Worker::Worker(QObject *parent)
    : QThread(parent)
{
    qDebug() << "Worker Thread:" << QThread::currentThreadId();
}

Worker::~Worker()
{
    qDebug() << "~Worker Thread:" << QThread::currentThreadId();
    
    /* 请求中止 */
    requestInterruption();
    /* 退出线程 */
    quit();
    /* 等待线程退出 */
    wait();
}

void Worker::run()
{
    qDebug() << "Worker Run Thread:" << QThread::currentThreadId();

    /* 是否请求中止 */
    while (!isInterruptionRequested())
    {
        QThread::sleep(1);
        qDebug() << "Hello world!";
    }
}

MainWindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

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;
};

#endif // MAINWINDOW_H

MainWindow.cpp

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

#include <QtWidgets>
#include "worker.h"

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    qDebug() << "Main Thread:" << QThread::currentThreadId();

    /* 当前窗口退出后，Worker线程自动退出 */
    Worker* worker = new Worker(this);
    worker->start();
}

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

打印结果

Main Thread: 0x10eaa9dc0
Worker Thread: 0x10eaa9dc0
Worker Run Thread: 0x7000027ba000
Hello world!
Hello world!
Hello world!
~Worker Thread: 0x10eaa9dc0
Hello world!