释放线程中new的套接字

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在做Symbian应用开发和MeeGo应用开发时Q框架是一个统一的开发框架,很多时候需要在QThread的run中new一个QUdpSocket来收发数据.这时,这个socket对象的释放就成了一个麻烦的问题.

如果在thread的析构中直接delete这个socket对象,则会出现如下异常:

QSocketNotifier: socket notifiers cannot be disabled from another thread  ASSERT failure in QCoreApplication::sendEvent: “Cannot send events to objects owned by a different thread. Current thread 560cb8. Receiver ” (of type ‘QNativeSocketEngine’) was created in thread a617748″, file kernel\qcoreapplication.cpp, line 349 Invalid parameter passed to C runtime function. Invalid parameter passed to C runtime function.

以下是解决方案:

◆在线程中定义一个线程释放的标识

◆在run()中用while来判断这个标识,以便于结束socket对象.

◆在thread的析构中,设定标识,并使用quit()和wait().

代码如下:


UdpSocketThread::UdpSocketThread(QObject *parent) :  QThread(parent) { this->socket = 0; this->needStop = false; }  UdpSocketThread::~UdpSocketThread() { this->needStop = true; quit(); wait(); }  void UdpSocketThread::run() { socket = new QUdpSocket; connect(socket,SIGNAL(readyRead()),this,SLOT(readPendingDatagrams())); socket->bind(2234); exec(); while(this->needStop) { if(this->socket) { delete this->socket; this->socket = 0; } break; } } 

这个线程对象的释放比较有代表性,应该可以解决很多类似的问题.

另外,方法可能还有其他的,这里只是举了一种而已.

其实,问题的关键就是:线程中创建的对象就必须在线程中释放.

PS:

经shiroki的指正,其实QT有更好的机制来释放对象.那就是deleteLater(). 于是,事情就显得非常简单,请看代码:

UdpSocketThread::UdpSocketThread(QObject *parent) :  QThread(parent) { socket = 0; }  UdpSocketThread::~UdpSocketThread() { this->socket->deleteLater(); quit(); wait(); }  void UdpSocketThread::run() { socket = new QUdpSocket; connect(socket,SIGNAL(readyRead()),this,SLOT(readPendingDatagrams())); socket->bind(2234); exec();  } 



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