c++ - QtNetwork:为什么我没有检测到传入的连接？ (永远不会触发传入的Connection())

我坚持使用有关线程qt网络的教程(在这里:http://doc.qt.io/qt-5/qtnetwork-threadedfortuneserver-example.html)，我做了一些小的更改并将其集成到我的主程序中。但是incomingConnection()永远不会执行，另一方面客户端可以进行连接。由于我想使用incomingConnection()，因此不再使用SIGNAL(newConnection())，但即使这样也无法正常工作。

有人知道出什么事了吗？

这是我的.h

#include <QtNetwork>
#include <QTcpServer>
#include <QTcpSocket>
#include <QThread>

class WirelessNetThread: public Thread
{
    Q_OBJECT

public:
    WirelessNetThread(int socketDescriptor, QObject * parent);

    void run() Q_DECL_OVERRIDE;

signals:
    void error(QTcpSocket::SocketError socketError);

private:
    int socketDescriptor;
    QString text;
};

class WirelessNet : public QTcpServer
{
    Q_OBJECT

public:
    WirelessNet(QObject *parent = 0);

protected:
    void incomingConnection(qintptr socketDescriptor) Q_DECL_OVERRIDE;

};

和.cpp

WirelessNetThread::WirelessNetThread(int socketDescriptor, QObject *parent):QThread(parent), socketDescriptor(socketDescriptor)
{
}

void WirelessNetThread::run()
{
    QTcpSocket tcpSocket;
    if ( !tcpSocket.setSocketDescriptor(socketDescriptor))
    {
        emit error(tcpSocket.error());
        return;
    }

    tcpSocket.disconnectFromHost();
    tcpSocket.waitForDisconnected();
}

WirelessNet::WirelessNet(QObject *parent): QTcpServer(0)
{
    listen(QHostAddress::Any, 5220);
    printf("is listening %d\n", this->isListening());
}

void WirelessNet::incomingConnection(qintptr socketDescriptor)
{
    qDebug() << "incomming \n";
    printf("incomming \n");
    WirelessNetThread *thread = new WirelessNetThread(socketDescriptor, this);
    connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater()));
    thread->start();
}

这是我的主程序的摘录，它是从那里开始的(顺便说一句，如果我不包括moveToThread()，则没有关系:

WirelessNet *wifi = new WirelessNet(this->parent());
wifi->moveToThread(this->thread());

如果在wifi初始化后添加以下行，即使这样也没有影响:

wifi = new WirelessNet(this->parent());
QEventLoop testLoop;
testLoop.exec();

换句话说，“输入”永远不会被打印出来，因此我无法继续工作。有谁知道，这几乎是本教程中1:1的代码，这让我感到困惑。

最佳答案

在您的主要代码中:

WirelessNet *wifi = new WirelessNet(0); // 0 = assign no parent
QThread *wifiThread = new QThread;
wifi->moveToThread(wifiThread);
QObject::connect(wifiThread, SIGNAL(started()), wifi, SLOT(startWifi()));
// start() will start its own event loop, it will emit started(), therefore startWifi() slot will be called.
wifiThread->start();

然后是您的WirelessNet类 header :

class WirelessNet : public QTcpServer
{
    Q_OBJECT

public:
    WirelessNet(QObject *parent = 0);

protected:
    void incomingConnection(qintptr socketDescriptor) Q_DECL_OVERRIDE;

public slots:
    void startWifi();
};

然后是您的WirelessNet类主体:

WirelessNet::WirelessNet(QObject *parent) :
    QTcpServer(parent)
{
    // Do nothing much here because we want to initialise new stuff in our thread.
    // When this function runs we have not moved this to the new thread - or even started it.
}

void WirelessNet::incomingConnection(qintptr socketDescriptor)
{
    qDebug() << "incomming \n";
    printf("incomming \n");
    WirelessNetThread *thread = new WirelessNetThread(socketDescriptor, this);
    connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater()));
    thread->start();
}

// Called when the thread has started
void WirelessNet::startWifi()
{
    // Anything done here is now safely within out new thread.
    listen(QHostAddress::Any, 5220);
    printf("is listening %d\n", this->isListening());
}

注释这是示例代码，我直接将其写到堆栈溢出中，但尚未编译，因此可能存在一些错误:)我已经评论了一些关键点，您在原始尝试中可能出错了。

关于c++ - QtNetwork:为什么我没有检测到传入的连接？ (永远不会触发传入的Connection())，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/36195654/