QThread: Move owner of thread to thread with moveToThread

[SepticInsect]

Thanks for the help! I will try the example in the link you sent.

[SepticInsect]

I have implemented my thread according to: http://mayaposch.wordpress.com/2011/...l-explanation/ and it works fine.
If I would like to stop my thread from the main thread (when the user presses Cancel) how shall I do that?

[ChrisW67]

It depends on what your thread is doing, but something like:

class Worker : public QObject {
    Q_OBJECT
public:
    Worker(): stopRequested(false) { }
    ~Worker() { }
 
public slots:
    void process() {
        while (1) {
            sleep(1);             // fake some uninteruptable work unit
 
            QMutexLocker lock(&mutex);
            if (stopRequested)
                break;
        }
       emit finished();
    }
 
public:
    void requestStop() {
        QMutexLocker lock(&mutex);
        stopRequested = true;
    }
 
signals:
    void finished();
private:
    QMutex mutex;
    bool stopRequested;
};

class Worker : public QObject {
    Q_OBJECT
public:
    Worker(): stopRequested(false) { }
    ~Worker() { }

public slots:
    void process() {
        while (1) {
            sleep(1);             // fake some uninteruptable work unit

            QMutexLocker lock(&mutex);
            if (stopRequested)
                break;
        }
       emit finished();
    }

public:
    void requestStop() {
        QMutexLocker lock(&mutex);
        stopRequested = true;
    }

signals:
    void finished();
private:
    QMutex mutex;
    bool stopRequested;
};

To copy to clipboard, switch view to plain text mode 

requestStop() can be called to schedule an orderly shut down of the thread.

[SepticInsect]

OK Thanks.
I have decided that i whould like to wait until may thread has finished instead of exiting the thread when the user presses Cancel. How can i implement that?

//Slot connected to finished signal of the worker class
void a::threadFinished() { 
  m_finished = true;
}
 
void a::cancelPressed() {
  //Here I would like to wait until the thread is finished.
  bool stopWaiting = false;
  while(!stopWaiting) {
    m_mutex.lock();
    if (m_finished)
      stopWaiting = true;
    m_mutex.unlock();
    //How shall I implement the delay (if stopWaiting is false) before i continue another loop in the whileloop without locking the entire program?
  }
 
  //Do som stuff after the thread has finished.
 
}

//Slot connected to finished signal of the worker class
void a::threadFinished() { 
  m_finished = true;
}

void a::cancelPressed() {
  //Here I would like to wait until the thread is finished.
  bool stopWaiting = false;
  while(!stopWaiting) {
    m_mutex.lock();
    if (m_finished)
      stopWaiting = true;
    m_mutex.unlock();
    //How shall I implement the delay (if stopWaiting is false) before i continue another loop in the whileloop without locking the entire program?
  }

  //Do som stuff after the thread has finished.

}

To copy to clipboard, switch view to plain text mode 

[ChrisW67]

Both the worker and the QThread issue a finished() signal when they are done. Connect to that signal and put your post-processing in the slot. Then you don't have to block the Qt event loop and GUI update.

[SepticInsect]

But I whould like to exit the entire program when the user presses Cancel. I would like to make sure the threads are finished before I exit the program.

[wysota]

But I whould like to exit the entire program when the user presses Cancel. I would like to make sure the threads are finished before I exit the program.

So when all threads are finished(), check if cancel was pressed, and if so, quit the application.

[SepticInsect]

Thanks everyone for the help! The problem is solved!