Hi all,

I'm new to threading in Qt.
I have several questions regarding the following class. I hope that wise programmers of this forum will help me better understand the QThread class and how does threads works in Qt.

thread1.h
Qt Code: 
  1. #ifndef THREAD1_H
  2. #define THREAD1_H
  3.  
  4. #include <QThread>
  5. #include <QTimer>
  6.  
  7. class Thread1 : public QThread
  8. {
  9.     Q_OBJECT
  10. public:
  11.     Thread1();
  12.     ~Thread1();
  13.  
  14. protected:
  15.     void run();
  16.  
  17. signals:
  18.     void sigThreadQuit();
  19.  
  20. public slots:
  21.     void sTimeout();
  22.  
  23. private:
  24.     QTimer* timer1;
  25.     QTimer timer2;
  26.  
  27.     int counter;
  28. };
  29.  
  30. #endif // THREAD1_H
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thread1.cpp
Qt Code: 
  1. #include "thread1.h"
  2.  
  3. Thread1::Thread1():
  4.         timer1(new QTimer(this)), counter(0)
  5. {
  6.     qDebug("Thread1(): Creating...");
  7.     timer1->setInterval(1000);
  8.     timer2.setInterval(1000);
  9.  
  10.     connect(timer1, SIGNAL(timeout()), this, SLOT(sTimeout()));
  11.     connect(&timer2, SIGNAL(timeout()), this, SLOT(sTimeout()));
  12.  
  13.     moveToThread(this);
  14. }
  15.  
  16. Thread1::~Thread1() {
  17.     qDebug("~Thread1(): Destroyed.");
  18. }
  19.  
  20. void Thread1::run() {
  21.     qDebug("Thread1::run(): Running...");
  22.     timer1->start();
  23.     timer2.start();
  24.     exec();
  25. }
  26.  
  27. void Thread1::sTimeout() {
  28.     QTimer* t = (QTimer*) sender();
  29.     qDebug("sTimeout(): Timer: %p; Counter: %d", t, counter);
  30.     if(counter > 10)
  31.         emit sigThreadQuit();
  32.     counter++;
  33. }
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main.cpp
Qt Code: 
  1. #include <QtCore/QCoreApplication>
  2.  
  3. #include "thread1.h"
  4. #include "thread2.h"
  5.  
  6. int main(int argc, char *argv[])
  7. {
  8.     QCoreApplication a(argc, argv);
  9.     qDebug("Main start");
  10.  
  11. //    Thread1* t1 = new Thread1();
  12.  
  13.     Thread1 t2;
  14.  
  15. //    Thread2 t2;
  16.  
  17.     //    a.connect(t1, SIGNAL(sigThreadQuit()), &a, SLOT(quit()));
  18.     a.connect(&t2, SIGNAL(sigThreadQuit()), &a, SLOT(quit()));
  19.  
  20. //    t1->start();
  21.     t2.start();
  22.  
  23.     int retvel = a.exec();
  24.  
  25.     qDebug("Main end");
  26.     return retvel;
  27. }
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The main function creates an object of class Thread1, which is designed to display text and after 10 seconds to send a signal to finish the thread.
After creating a t2 object, signal sending by a thread is connected with the slot quit() of the main application.
In the above class, I have two objects QTimer - one of them is a pointer.
After running the application I see that only one timer is working - a pointer.

Here are my questions:
1. Why I can not see the operation of the QTimer object which is not a pointer? Does is not running?
2. If I don't use function moveToThread() for instance in the constructor of Thread1 class, then QTimer objects (or a thread), do not start in general. I think that it has something with main a.exec() function. Why and what?
3. Does the above example is written correctly with the principles of multithreaded programming in Qt?

I wrote this class for understanding Qt thread support. Any posts with good explanations and links are welcome.

Thank you for any answers