I am not new in Posix threads but new in QThread. The expected behaviour of my code is both threads increasing a shared variable named val. Unfortunately it appears that each one is working on a different instance of val, ie if I clic twice on button 1 I get val=2 and then if I clic on button 2 I get val=0.
What is wrong in my code?
Thanks in advance for your help.

Qt Code: 
  1. class boutonThread : public QThread
  2. {
  3.   Q_OBJECT
  4.  
  5. public:
  6.   boutonThread(QWidget *parent = 0, int number = 0);
  7.  
  8. public slots:
  9.   void threadClicked();
  10.  
  11. private:
  13.   int val;
  14.   QVector<long> thread_ids;
  15.   int GetId();
  16. };
  17.  
  18. class boutons : public QWidget
  19. {
  20.   Q_OBJECT
  21.  
  22. public:
  23.   boutons(QWidget *parent = 0);
  24.  
  25. private:
  26.   QPushButton *buttons[2];
  27.   buttonThread *threads[2];
  28. };
  29.  
  30. boutons::boutons(QWidget *parent)
  31. {
  32.   QHBoxLayout *layout = new QHBoxLayout(this);
  33.   buttons[0] = new QPushButton("Thread 1", this);
  34.   layout->addWidget(buttons[0]);
  35.   threads[0] = new boutonThread(this, 1);
  36.   QObject::connect(this->buttons[0], SIGNAL(clicked()), threads[0], SLOT(threadClicked()));
  37.   buttons[1] = new QPushButton("Thread 2", this);
  38.   layout->addWidget(buttons[1]);
  39.   threads[1] = new boutonThread(this, 2);
  40.   QObject::connect(this->buttons[1], SIGNAL(clicked()), threads[1], SLOT(threadClicked()));
  41.   threads[0]->start();
  42.   threads[1]->start();
  43. }
  44.  
  45. boutonThread::boutonThread(QWidget *parent, int number)
  46. {
  47.   this->thread_ids.resize(2);
  48.   this->thread_ids[number-1] = (long)QThread::currentThread();
  49.   this->val = 0;
  50. }
  51.  
  52. int
  53. boutonThread::GetId()
  54. {
  55.   return this->thread_ids.indexOf((long)QThread::currentThread()) + 1;
  56. }
  57.  
  58. void
  59. boutonThread::threadClicked()
  60. {
  61.   QMessageBox *msg = new QMessageBox(QMessageBox::NoIcon, QString(), QString("Thread %1 : val = %2").arg(this->GetId()).arg(this->val), QMessageBox::Ok);
  62.   this->val++;
  63.   msg->exec();
  64. }
To copy to clipboard, switch view to plain text mode