QThread之moveToThread用法

简介

使用moveToThread函数的流程如下：
1、创建一个类继承自QObject类或其子类，并在其中定义所要执行的多个任务，执行多个任务就要定义相应的信号。
2、任务通过moveToThread指定所要执行的线程。
3、线程通过start启动
4、通过信号与槽机制触发线程的执行

为什么要用

适用场景：

适合单次任务执行，即有点像懒人，触发一下，干一次活
适合干完活，需要主动推送一个通知
适合用于简化多线程中，对数据安全的保护

它不适用的场景:

不适用高频率任务，即跑完一个任务，可能没有时间休息，持续跑
执行高频率任务，还是需要使用重写QThread::run()的方式，来实现

示例一个循环读取进度条的模型
在这里插入图片描述

1.首先定义我们的worker
头文件

//
// Created by zhe.xiao on 2023/12/05.
//#pragma once#include "std_include.h"
#include <QObject>class OperationWorker : public QObject
{
Q_OBJECT
public:explicit OperationWorker(QObject* parent = nullptr);~OperationWorker();signals:void SendRecordImportProgress(QString ecgPath);public slots:void ProcessRecordImportProgress(QString ecgPath);
};

cpp文件

//
// Created by zhe.xiao on 2023/12/05.
//#include "operation_worker.h"
#include <QThread>OperationWorker::OperationWorker(QObject* parent) : QObject(parent)
{}OperationWorker::~OperationWorker()
{}void OperationWorker::ProcessRecordImportProgress(QString ecgPath)
{qDebug("===OperationWorker ProcessRecordImportProgress, ecgPath=%s", ecgPath.toStdString().c_str());int i = 0;while (i <= 100){std::string percent = std::to_string(i) + "%";emit SendRecordImportProgress(QString(percent.c_str()));i += 15;}
}

2.定义一个控制器，专门来控制worker

头文件
//
// Created by zhe.xiao on 2023/12/05.
//#pragma once#include "std_include.h"
#include "operation_worker.h"
#include <QObject>
#include <QThread>class OperationController : public QObject
{
Q_OBJECT
public:explicit OperationController(QObject* parent = nullptr);~OperationController() override;//触发读取记录仪进度条void StartRecordImportProgress();signals:void TriggerRecordImportProgress(QString ecgPath);public slots:void ReceiveRecordImportProgress(QString percent);private:QThread m_workThread;
};

cpp文件

//
// Created by zhe.xiao on 2023/12/05.
//#include "operation_controller.h"OperationController::OperationController(QObject* parent) : QObject(parent)
{auto operationWorker = new OperationWorker();operationWorker->moveToThread(&m_workThread);//绑定事件connect(&m_workThread, &QThread::finished, operationWorker, &QObject::deleteLater);connect(this, &OperationController::TriggerRecordImportProgress, operationWorker, &OperationWorker::ProcessRecordImportProgress);connect(operationWorker, &OperationWorker::SendRecordImportProgress, this, &OperationController::ReceiveRecordImportProgress);//线程启动m_workThread.start();
}OperationController::~OperationController()
{m_workThread.quit();m_workThread.wait();
}void OperationController::StartRecordImportProgress()
{emit TriggerRecordImportProgress("xiaozhe");
}void OperationController::ReceiveRecordImportProgress(QString percent)
{qDebug("===OperationController ReceiveRecordImportProgress, percent=%s", percent.toStdString().c_str());
}

注：由于Worker是QObject对象，同时通过connect(&thread, &QThread::finished, operationWorker, &QObject::deleteLater)建立信号槽；当线程释放时，会自动删除Worker对象，并不会内存泄漏。

3.外部函数触发执行

int OperationRecorderImport::Test()
{auto operationController = new OperationController();;operationController->StartRecordImportProgress();return OPERATION_SUCCESS;
}