c – 是否可以使用QThread实现轮询而无需对其进行子类化？

class Device  
{  
public:  
  ...  
  void Start();  
  void Stop();  
  void MsgLoop();

signals:
  void sMsgArrived();
}

void MsgLoop()  
{
   forever {  
      if(succesS == ReadMsg()) //synchronous,non-blocking
      {
        ProcessMsg(); //quite fast
        emit sMsgArrived(); //this signal is connected with a slot in GUI thread  
      }
   }
}

解决方法

class Device : QObject
{
    Q_OBjeCT
public:
    Device(QObject * parent = null);
    void Start();  
    void Stop();  

private slots:
    void MsgLoop();

signals:
    void sMsgArrived();

private:
    QThread thread;
    bool stopThread;
};


Device::Device(QObject * parent) : QObject(parent)
{
    moveToThread(&thread);
    connect(&thread,SIGNAL(started()),this,SLOT(MsgLoop()));
}

void Device::Start()
{
    stopThread = false;
    thread.start();
}

void Device::Stop()
{
    stopThread = true;
    thread.wait();      // if you want synchronous stop
}

void Device::MsgLoop()
{
  // your loop
  while(!stopThread)
    if(succesS == ReadMsg())
    {
      ProcessMsg();
      emit sMsgArrived();
    }
  QThread::currentThread->quit();
}

注意：只有在ReadMsg确实是非阻塞的情况下,线程停止才有效.如果你以后决定切换到阻塞读取(这可能适用于大多数情况),你将不得不找到另一种方法来阻止你的线程.@H_262_10@