对qt多线程以及事件投递的理解20200730

代码如下：

MyObject.h

#pragma once

#include <QObject>
#include <QEvent>

const QEvent::Type CustomEvent_Login = (QEvent::Type)5001; //! 建议用5000以上唯一的标识

class MyObject : public QObject
{
	Q_OBJECT

public:
	MyObject();
	~MyObject();

protected slots:
	void Started();
	void Timeout();

private:
	void customEvent(QEvent *e); //! 重载QObject的续虚函数
};

MyObject.cpp 

#include "MyObject.h"
#include <QDebug>
#include <QThread>

MyObject::MyObject()
{
}

MyObject::~MyObject()
{
}

void MyObject::Started()
{
	qDebug() << "Started:" << (qlonglong)QThread::currentThreadId();
}

void MyObject::Timeout()
{
	qDebug() << "Timeout:" << (qlonglong)QThread::currentThreadId();
}

void MyObject::customEvent(QEvent *e)
{
	if (e->type() == CustomEvent_Login)//捕获消息
	{
		qDebug() << QString("[%1]catch the event: %2!").arg((qlonglong)QThread::currentThreadId()).arg(e->type());
	}
}

Main.cpp

#include <QtCore/QCoreApplication>
#include <QThread>
#include <QDebug>
#include <QObject>
#include <QTimer>
#include "MyObject.h"

int main(int argc, char *argv[])
{
	QCoreApplication a(argc, argv);

	qDebug() << "main:" << (qlonglong)QThread::currentThreadId();

	//! 业务逻辑对象
	MyObject* myObj = new MyObject;

	//! 线程-->新的线程
	QThread *thread = new QThread();
	//! 定时器
	QTimer *timer = new QTimer();

	//! 把业务逻辑对象设置进线程，不要把Qthread放进自己线程，这样的写法不建议。
	myObj->moveToThread(thread);

	//! 线程启动
	thread->start();

	//! 绑定的时候最好设置QueuedConnection。这样就允许在myObj线程执行，否则可能会在主线程执行。
	//! 如果希望不要再子线程执行，用DirectConnection。

	QObject::connect(thread, SIGNAL(started()), myObj, SLOT(Started()), Qt::QueuedConnection);

	QObject::connect(timer, SIGNAL(timeout()), myObj, SLOT(Timeout()), Qt::QueuedConnection);

	//! 定时器启动
	timer->start(1000);
	//! 发送事件
	QCoreApplication::postEvent(myObj, new QEvent(CustomEvent_Login));
	qDebug() << QString("[%1]send the event: %2!")
		.arg((qlonglong)QThread::currentThreadId())
		.arg(CustomEvent_Login);

	//! MyObject::Started/MyObject::Timeout/都会在同一个子线程调用。

	return a.exec();
}