Qt move to thread 移动到新线程注意事项

使用move to thread接口将某个类移动到新线程时，该类中如果有指针成员变量的话，也要把指针成员变量一起移动到新线程内，不然指针的成员变量还在主线程，特别的tcp、tdp等比较耗时的对象。

先移动类的对象，再移动类的指针成员变量。

类指针的初始化在移动到新线程前做就可以。

自己写了一个测试udp发送接收的类。用socket助手向发送数据，用自己的程序接收。来测试udp在多线程下的表现。

	this->init();
	this->moveToThread(&m_thread);
	this->m_receiveSocket->moveToThread(&m_thread);
	m_thread.start();

这段代码在一个类的构造函数里面，类中函数udp的socekt指针。

如果不把m_receiveSocket也移动到新线程。就会出现下面的错误：

并且udp只能收到一次数据，其余的全部就收不到了。

移动到新线程后，就是这样的结果。

数据接收正常。下面贴上完整源码。

udpReceiveTest .h:

#pragma once

#include 
#include 
#include 

class udpReceiveTest : public QObject
{
	Q_OBJECT
public:
	QThread m_thread;

public:
	udpReceiveTest(QObject *parent);
	udpReceiveTest(const QString &bindIp, const int port);

	~udpReceiveTest();


public:
	void slot_readyRead();


	void init();	
private:
	QUdpSocket *m_receiveSocket;
	QString m_bindIp;
	int m_bindPort;
};

udpReceiveTest.cpp:

#include "udpReceiveTest.h"
#include 
#include 

udpReceiveTest::udpReceiveTest(QObject *parent)
	: QObject(parent)
{
}
udpReceiveTest::udpReceiveTest(const QString &bindIp, const int port)
{
	this->m_bindIp = bindIp;
	this->m_bindPort = port;

	this->init();
	this->moveToThread(&m_thread);
	this->m_receiveSocket->moveToThread(&m_thread);
	m_thread.start();
}


udpReceiveTest::~udpReceiveTest()
{
}

void udpReceiveTest::slot_readyRead()
{

	QString data;

	while (this->m_receiveSocket->hasPendingDatagrams()) {
		QNetworkDatagram datagram = m_receiveSocket->receiveDatagram();
		data += datagram.data();	
	}

	qDebug() << "receive data :" << data;
	qDebug() << "udp thread id:" << QThread::currentThreadId();
	
}

void udpReceiveTest::init()
{
	this->m_receiveSocket = new QUdpSocket();

	this->m_receiveSocket->bind(QHostAddress(m_bindIp), m_bindPort);

	connect(this->m_receiveSocket, &QUdpSocket::readyRead, this, &udpReceiveTest::slot_readyRead);

	qDebug() << "init thread id is " << QThread::currentThreadId();
}

main.cpp:

#include 
#include 
#include 

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

	qDebug() << "main thread id:" << QThread::currentThreadId();

	udpReceiveTest socket(("127.0.0.1"), 21);

	return a.exec();
}