QTimer in a worker thread

Hi,

I have problems with starting a QTimer or singleshot in a worker thread. Is that true that the timers only will start in the main thread?

My main start an object startIntegrator, that is a QObject. This object start a new thread called FB_thread (QThread). The run() of this thread go to a function , called receiveMsg(), that check if something come to a defined com-port. I want to count these incomming bytes. I want to start a timer when the run()-function receive something. When this timer timeout(), I want to put the counter to zero.

I want to put the reading function in a thread because I will have several threads to read an put into several queues.
My communication procedure with the commPort is qextserialcommport.

In addition to that timer mentioned, I want to start a timer that go into FB_thread's .
I use Ubuntu OS.

My question is:
Where do I put the counter, and how?

I have tried several places in my program, but the Timer will not be set to zero.
My last try is like this:

Code:

---

startIntegrator::startIntegrator(QObject *parent) :
    QObject(parent)
{
    FB_thread = new Flex_thread;
    FB_thread->start();
 
    flexiTimer = new QTimer();
    flexiTimer->setInterval(5);
    flexiTimer->start();
 
    connect(flexiTimer, SIGNAL(timeout()), FB_thread, SLOT(checkFlexiCommPort()));
    connect(flexiTimer, SIGNAL(timeout()), FB_thread, SLOT(flexiTimerSignal()));
    connect(FB_thread, SIGNAL(setCounterToZero()), this, SLOT(startReceiverTimer()));
    connect(this->updateCounterTimer, SIGNAL(timeout()), FB_thread, SLOT(updateCounter()));
    connect(flexiTimer, SIGNAL(timeout()), this, SLOT(startUpRoutine()));
    FBToFLTP->wait();
    FB_thread->wait();
}
 
void startIntegrator::startReceiverTimer()
{
    qDebug() << "startReceiverTimer()";
    updateCounterTimer = new QTimer();
    updateCounterTimer->start(0);
}
 
void startIntegrator::startUpRoutine()
{
    FB_thread->checkFlexiCommPort();
}

---

And the Flex_thread is:

Code:

---

Flex_thread::Flex_thread(QObject *parent) :
    QThread(parent)
{
    flexiCommPortNumber = "/dev/ttyUSB0";
    // some code...
    connect(this, SIGNAL(setCounterToZero()), this, SLOT(checkSignal()));
}
 
void Flex_thread::run()
{
    do
    {
        receiveMsg();
    }while(!stopped);
}
 
void Flex_thread::checkSignal()
{
    qDebug() << "Signal ok!!"; // Just for checking that this is used
}
 
void Flex_thread::receiveMsg()
{
    int numBytes = CommPort->bytesAvailable();  // Check if the data is there   
    if(numBytes > 0)                            
    {
        emit this->setCounterToZero();                   // When something comes to this part of the program, I want to reset counterBytes after 1 sec.
                                                                     // I have tried to initiate and start a counter here also
        if (numBytes > 20) numBytes = 20;           
        char buff[20];                             
        CommPort->readData(buff, numBytes);         // Read bytes from CommPort
 
        counterBytes = counterBytes + numBytes;
 
        // ... Here I take care of the incomming data  
   } 
} 
void Flex_thread::updateCounter()
{
    counterBytes = 0;
}
void Flex_thread::checkFlexiCommPort()
{
    // do something
}

---

Can someone help me with these timers?

You can start timer in any thread but in Flex_thread it will be not working because You don't start event loop in method Flex_thread::run.
Look at the source of QThread::run.

I want to start a QTimer::singleShot in line 28 in FlexThread.
I do not manage to start it. I have tried to put in following line:
QTimer::singleShot(1000, this, SLOT(updateCounter()));

while updateCounter() set the counterBytes to 0.

I have also put exec() between line 14 and 15 in Flex_thread. But I think the timer will not start. The updateCounter() will not start.

How may I do this?

Quote:

---

Originally Posted by inger

I have also put exec() between line 14 and 15 in Flex_thread.

---

Please think for a short while when this line is going to be executed.

Oh sorry,
that will never be executed.:(

Are you able to help me how to get the QTimer started?

Read this: [wiki]Keeping the GUI Responsive[/wiki]

Quote:

---

Originally Posted by inger

I want to start a QTimer::singleShot in line 28 in FlexThread.
I do not manage to start it. I have tried to put in following line:
QTimer::singleShot(1000, this, SLOT(updateCounter()));

while updateCounter() set the counterBytes to 0.

I have also put exec() between line 14 and 15 in Flex_thread. But I think the timer will not start. The updateCounter() will not start.

How may I do this?

---

Thanks for the post... I really like the answer..