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Forum Update on Monday, May 27th 2025

QTimer make traitement out of for loop ?

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  • I imene

    @SGaist is there a way more easy than that ? with another type of timer ?
    can i use this signal void QTimer::timeout()?

    M Offline
    M Offline
    mpergand
    wrote on last edited by mpergand
    #14

    @imene
    For your long delay, you can use lambda as well,
    Although I don't see any real benefit with it.

    1 Reply Last reply
    0
    • I Offline
      I Offline
      imene
      wrote on last edited by
      #15

      @mpergand
      What do you mean with lamba ?

      jsulmJ 1 Reply Last reply
      0
      • I imene

        @mpergand
        What do you mean with lamba ?

        jsulmJ Offline
        jsulmJ Offline
        jsulm
        Lifetime Qt Champion
        wrote on last edited by
        #16

        @imene C++ lambda functions: https://en.cppreference.com/w/cpp/language/lambda

        https://forum.qt.io/topic/113070/qt-code-of-conduct

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        • I Offline
          I Offline
          imene
          wrote on last edited by
          #17

          QTimer::singleShot :This static function calls a slot after a given time interval; in my case i want the code to make the traitement inside QTimer::singleShot before it pass to make the next if condition .

          Christian EhrlicherC 1 Reply Last reply
          0
          • I imene

            QTimer::singleShot :This static function calls a slot after a given time interval; in my case i want the code to make the traitement inside QTimer::singleShot before it pass to make the next if condition .

            Christian EhrlicherC Offline
            Christian EhrlicherC Offline
            Christian Ehrlicher
            Lifetime Qt Champion
            wrote on last edited by
            #18

            @imene said in QTimer make traitement out of for loop ?:

            to make the traitement inside QTimer::singleShot before it pass to make the next if condition .

            Let the QTimer::singleShot() fire and check for your codition inside the slot.

            Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
            Visit the Qt Academy at https://academy.qt.io/catalog

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            • I Offline
              I Offline
              imene
              wrote on last edited by
              #19

              @Christian-Ehrlicher how ?

              Christian EhrlicherC 1 Reply Last reply
              0
              • I imene

                @Christian-Ehrlicher how ?

                Christian EhrlicherC Offline
                Christian EhrlicherC Offline
                Christian Ehrlicher
                Lifetime Qt Champion
                wrote on last edited by Christian Ehrlicher
                #20

                @imene said in QTimer make traitement out of for loop ?:

                how ?

                if (yourCoditionIsMet) {
                  doSomethingYouWant()
                }
                

                maybe?

                Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                Visit the Qt Academy at https://academy.qt.io/catalog

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                • I Offline
                  I Offline
                  imene
                  wrote on last edited by
                  #21

                  @Christian-Ehrlicher
                  my condition is to wait for QTimer::singleShot() to be executed

                  Christian EhrlicherC 1 Reply Last reply
                  0
                  • I imene

                    @Christian-Ehrlicher
                    my condition is to wait for QTimer::singleShot() to be executed

                    Christian EhrlicherC Offline
                    Christian EhrlicherC Offline
                    Christian Ehrlicher
                    Lifetime Qt Champion
                    wrote on last edited by
                    #22

                    @imene said in QTimer make traitement out of for loop ?:

                    my condition is to wait for QTimer::singleShot() to be executed

                    Why?
                    If you want to stop a timer, use a QTimer object and stop it if you want.

                    Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                    Visit the Qt Academy at https://academy.qt.io/catalog

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                    • I Offline
                      I Offline
                      imene
                      wrote on last edited by
                      #23

                      This timer

                      connect(m_speedTimer, &QTimer::timeout, this, &MainWindow::on_Send_Row_Button_clicked);
                      
                      
                       if( trameRecu[0]==trameTest[0]){
                                      qDebug() <<"Test FF good!"; //model dialogue informing
                                      mModel->item(b, 4)->setText("FF");//ack
                                     
                      
                                      m_speedTimer->start(8000);
                      
                      
                                             QTimer::singleShot(7000, [=](){
                                          qDebug()<<"Timer on do something after 7000 msec...";
                      
                      
                                      if((Send_Frame_Get_ACK_Function(SetPayloadRPM))=="FF")
                      
                                      { qDebug()  << "Send_Frame_Get_ACK_Function Pass" ;
                      
                                          QString MySpeed=0;
                      
                                        MySpeed = Send_Frame_Get_Speed_Function(NSetPayload); //SetPayloadMem="F504"
                                        qDebug()  << " MySpeed" <<MySpeed;
                      
                                        double MSpeed = MySpeed.toFloat();
                                          qDebug()  << " MSpeed" <<MSpeed;
                                        bool result = ((MSpeed >= 40) && (MSpeed <= 60));
                                                qDebug() << "((MSpeed >= 40) && (MSpeed <= 60))" << result;
                                                result = ((MSpeed >= 90) && (MSpeed <= 110)  );
                                                qDebug() << "((MSpeed >= 90) && (MSpeed <= 110))" << result;
                                                result = ((MSpeed >= 490) && (MSpeed <= 520)  );
                                                qDebug() << "((MSpeed >= 490) && (MSpeed <= 520))" << result;
                      
                                        if ((MSpeed > 40) && (MSpeed < 60)  )
                      
                                        {mModel->item(b, 6)->setText("+50");}//result
                      
                                        else if ((MSpeed > 90) && (MSpeed < 110))
                                        {mModel->item(b, 6)->setText("+100");}//result
                      
                                        else if ((MSpeed > 140) && (MSpeed < 160))
                                        {mModel->item(b, 6)->setText("+150");}//result
                      
                                        else if ((MSpeed > 190) && (MSpeed < 210))
                                        {mModel->item(b, 6)->setText("+200");}//result
                      
                                        else if ((MSpeed > 240) && (MSpeed < 260))
                                        {mModel->item(b, 6)->setText("+100");}//result
                      
                                        else if ((MSpeed > 290) && (MSpeed < 310))
                                        {mModel->item(b, 6)->setText("+100");}//result
                      
                      
                                        else if ((MSpeed >490) && (MSpeed < 520))
                                        {mModel->item(b, 6)->setText("+500");}//result
                                        else
                                        {mModel->item(b, 6)->setText("Error");
                                        qDebug()  << " MSpeed if" <<MSpeed;}//result
                      
                      
                                      }
                      
                                      m_speedTimer->stop();
                      
                                     });//singleshot timer here
                      
                                  }
                      

                      m_speedTimer->start(8000);
                      repeat the traitement under it each 8000 but when i use m_speedTimer->stop(); it make traitement one time and stops without waiting 8000 msec!
                      I need a timer that make traitement after 8000msec.

                      Christian EhrlicherC 1 Reply Last reply
                      0
                      • I imene

                        This timer

                        connect(m_speedTimer, &QTimer::timeout, this, &MainWindow::on_Send_Row_Button_clicked);
                        
                        
                         if( trameRecu[0]==trameTest[0]){
                                        qDebug() <<"Test FF good!"; //model dialogue informing
                                        mModel->item(b, 4)->setText("FF");//ack
                                       
                        
                                        m_speedTimer->start(8000);
                        
                        
                                               QTimer::singleShot(7000, [=](){
                                            qDebug()<<"Timer on do something after 7000 msec...";
                        
                        
                                        if((Send_Frame_Get_ACK_Function(SetPayloadRPM))=="FF")
                        
                                        { qDebug()  << "Send_Frame_Get_ACK_Function Pass" ;
                        
                                            QString MySpeed=0;
                        
                                          MySpeed = Send_Frame_Get_Speed_Function(NSetPayload); //SetPayloadMem="F504"
                                          qDebug()  << " MySpeed" <<MySpeed;
                        
                                          double MSpeed = MySpeed.toFloat();
                                            qDebug()  << " MSpeed" <<MSpeed;
                                          bool result = ((MSpeed >= 40) && (MSpeed <= 60));
                                                  qDebug() << "((MSpeed >= 40) && (MSpeed <= 60))" << result;
                                                  result = ((MSpeed >= 90) && (MSpeed <= 110)  );
                                                  qDebug() << "((MSpeed >= 90) && (MSpeed <= 110))" << result;
                                                  result = ((MSpeed >= 490) && (MSpeed <= 520)  );
                                                  qDebug() << "((MSpeed >= 490) && (MSpeed <= 520))" << result;
                        
                                          if ((MSpeed > 40) && (MSpeed < 60)  )
                        
                                          {mModel->item(b, 6)->setText("+50");}//result
                        
                                          else if ((MSpeed > 90) && (MSpeed < 110))
                                          {mModel->item(b, 6)->setText("+100");}//result
                        
                                          else if ((MSpeed > 140) && (MSpeed < 160))
                                          {mModel->item(b, 6)->setText("+150");}//result
                        
                                          else if ((MSpeed > 190) && (MSpeed < 210))
                                          {mModel->item(b, 6)->setText("+200");}//result
                        
                                          else if ((MSpeed > 240) && (MSpeed < 260))
                                          {mModel->item(b, 6)->setText("+100");}//result
                        
                                          else if ((MSpeed > 290) && (MSpeed < 310))
                                          {mModel->item(b, 6)->setText("+100");}//result
                        
                        
                                          else if ((MSpeed >490) && (MSpeed < 520))
                                          {mModel->item(b, 6)->setText("+500");}//result
                                          else
                                          {mModel->item(b, 6)->setText("Error");
                                          qDebug()  << " MSpeed if" <<MSpeed;}//result
                        
                        
                                        }
                        
                                        m_speedTimer->stop();
                        
                                       });//singleshot timer here
                        
                                    }
                        

                        m_speedTimer->start(8000);
                        repeat the traitement under it each 8000 but when i use m_speedTimer->stop(); it make traitement one time and stops without waiting 8000 msec!
                        I need a timer that make traitement after 8000msec.

                        Christian EhrlicherC Offline
                        Christian EhrlicherC Offline
                        Christian Ehrlicher
                        Lifetime Qt Champion
                        wrote on last edited by
                        #24

                        @imene said in QTimer make traitement out of for loop ?:

                        t make traitement one time and stops without waiting 8000 msec!

                        Then remember that you want to stop your timer after the next timeout and stop it then.

                        Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                        Visit the Qt Academy at https://academy.qt.io/catalog

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                        • I Offline
                          I Offline
                          imene
                          wrote on last edited by
                          #25

                          What does m_speedTimer->start(8000); and m_speedTimer->stop(); do exactely ?

                          Christian EhrlicherC 1 Reply Last reply
                          0
                          • I imene

                            What does m_speedTimer->start(8000); and m_speedTimer->stop(); do exactely ?

                            Christian EhrlicherC Offline
                            Christian EhrlicherC Offline
                            Christian Ehrlicher
                            Lifetime Qt Champion
                            wrote on last edited by Christian Ehrlicher
                            #26

                            @imene said in QTimer make traitement out of for loop ?:

                            What does m_speedTimer->start(8000); and m_speedTimer->stop(); do exactely ?

                            Really??

                            RTM https://doc.qt.io/qt-6/qtimer.html

                            Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                            Visit the Qt Academy at https://academy.qt.io/catalog

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                            • I Offline
                              I Offline
                              imene
                              wrote on last edited by imene
                              #27

                              I want a timer that stop reading the code for 7sec then complete and execute the function, because singleShot timer execute function after 7 sec here:

                              QTimer::singleShot(7000, [=](){
                                                  qDebug()<<"Timer on do something after 6 second...";
                              
                              
                                             // i want to set a time out condition here
                              
                                             });//timer ends here
                              
                              Christian EhrlicherC 1 Reply Last reply
                              0
                              • I imene

                                I want a timer that stop reading the code for 7sec then complete and execute the function, because singleShot timer execute function after 7 sec here:

                                QTimer::singleShot(7000, [=](){
                                                    qDebug()<<"Timer on do something after 6 second...";
                                
                                
                                               // i want to set a time out condition here
                                
                                               });//timer ends here
                                
                                Christian EhrlicherC Offline
                                Christian EhrlicherC Offline
                                Christian Ehrlicher
                                Lifetime Qt Champion
                                wrote on last edited by
                                #28

                                @imene said in QTimer make traitement out of for loop ?:

                                qDebug()<<"Timer on do something after 6 second...";

                                QTimer::singleShot(7000, ={

                                Maybe you should at least add a correct comment...

                                We already told you how to start a timer, how to stop it and how you set a (member) variable to not execute something if this variable is set to a certain value is nothing we need to discuss here - it's a task for a c++ beginners book.

                                Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                                Visit the Qt Academy at https://academy.qt.io/catalog

                                1 Reply Last reply
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                                • I Offline
                                  I Offline
                                  imene
                                  wrote on last edited by
                                  #29

                                  what i have to do ?

                                  QObject::connect(m_speedTimer,&QTimer::timeout, this, &MainWindow::sendFrame,Qt::AutoConnection);
                                  
                                  void MainWindow::sendFrame(QString IdData_R,QString PayloadData_R,int i)
                                  {
                                  
                                              if (m_canDevice)
                                          {   m_speedTimer->start(6000);
                                          ...
                                           }
                                  
                                  }
                                  
                                  void MainWindow::on_SendAll_Button_clicked()
                                  {int a= m_ui->Table_CSV->model()->rowCount();
                                   for(int i=0;i<a; i++) //R :read , W :write
                                      { sendFrame(IdData_R, PayloadData_R,i);//});
                                       }
                                      
                                      m_speedTimer->stop();
                                      
                                   }
                                  

                                  513347e1-0444-4877-aa5d-fbcd337e5af2-image.png

                                  M 1 Reply Last reply
                                  0
                                  • I imene

                                    what i have to do ?

                                    QObject::connect(m_speedTimer,&QTimer::timeout, this, &MainWindow::sendFrame,Qt::AutoConnection);
                                    
                                    void MainWindow::sendFrame(QString IdData_R,QString PayloadData_R,int i)
                                    {
                                    
                                                if (m_canDevice)
                                            {   m_speedTimer->start(6000);
                                            ...
                                             }
                                    
                                    }
                                    
                                    void MainWindow::on_SendAll_Button_clicked()
                                    {int a= m_ui->Table_CSV->model()->rowCount();
                                     for(int i=0;i<a; i++) //R :read , W :write
                                        { sendFrame(IdData_R, PayloadData_R,i);//});
                                         }
                                        
                                        m_speedTimer->stop();
                                        
                                     }
                                    

                                    513347e1-0444-4877-aa5d-fbcd337e5af2-image.png

                                    M Offline
                                    M Offline
                                    mpergand
                                    wrote on last edited by
                                    #30

                                    @imene
                                    your code doesn't make sense.
                                    What do you want to do,
                                    send a frame every 6s ?

                                    1 Reply Last reply
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