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Text is not updated in qwidget.

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  • S sootoo23

    @jsulm

    I need to pass the char buffer of "keypadBuf" to the C library.
    It can not pass in the type of QString.

    jsulmJ Offline
    jsulmJ Offline
    jsulm
    Lifetime Qt Champion
    wrote on last edited by jsulm
    #6

    @sootoo23

    keypadBuf = SetValue.toLocal8Bit().data();
    

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

    S 1 Reply Last reply
    0
    • jsulmJ jsulm

      @sootoo23

      keypadBuf = SetValue.toLocal8Bit().data();
      
      S Offline
      S Offline
      sootoo23
      wrote on last edited by
      #7

      @jsulm
      Thank you for your feedback.
      Is there a solution to my problem?

      jsulmJ 1 Reply Last reply
      0
      • S sootoo23

        @jsulm
        Thank you for your feedback.
        Is there a solution to my problem?

        jsulmJ Offline
        jsulmJ Offline
        jsulm
        Lifetime Qt Champion
        wrote on last edited by jsulm
        #8

        @sootoo23 Is this label visible? Does it already have any text? Also, what are you doing after setting the text - do you maybe block the event loop with a loop?
        Did you check what SetValue contains?

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

        S 1 Reply Last reply
        0
        • jsulmJ jsulm

          @sootoo23 Is this label visible? Does it already have any text? Also, what are you doing after setting the text - do you maybe block the event loop with a loop?
          Did you check what SetValue contains?

          S Offline
          S Offline
          sootoo23
          wrote on last edited by
          #9

          @jsulm said in Text is not updated in qwidget.:

          Is this label visible? Does it already have any text? Also, what are you doing after setting the text - do you maybe block the event loop with a loop?
          Did you check what SetValue contains?

          yes, it is visible.

          The default text is displayed when you load the initial QWidget.
          The problem is that if you change the value by the number of characters, it will not update.

          "printf("%s (%s)\n", keypadBuf, SetValue.toLocal8Bit().data());"
          data is output well.

          jsulmJ 1 Reply Last reply
          0
          • S sootoo23

            @jsulm said in Text is not updated in qwidget.:

            Is this label visible? Does it already have any text? Also, what are you doing after setting the text - do you maybe block the event loop with a loop?
            Did you check what SetValue contains?

            yes, it is visible.

            The default text is displayed when you load the initial QWidget.
            The problem is that if you change the value by the number of characters, it will not update.

            "printf("%s (%s)\n", keypadBuf, SetValue.toLocal8Bit().data());"
            data is output well.

            jsulmJ Offline
            jsulmJ Offline
            jsulm
            Lifetime Qt Champion
            wrote on last edited by
            #10

            @sootoo23 Do you block the event loop somewhere?

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

            S 1 Reply Last reply
            0
            • jsulmJ jsulm

              @sootoo23 Do you block the event loop somewhere?

              S Offline
              S Offline
              sootoo23
              wrote on last edited by
              #11

              @jsulm

              I do not know what blocking an event loop is.

              jsulmJ 1 Reply Last reply
              0
              • S sootoo23

                @jsulm

                I do not know what blocking an event loop is.

                jsulmJ Offline
                jsulmJ Offline
                jsulm
                Lifetime Qt Champion
                wrote on last edited by
                #12

                @sootoo23 Do you have any endless loops?

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

                S 1 Reply Last reply
                1
                • jsulmJ jsulm

                  @sootoo23 Do you have any endless loops?

                  S Offline
                  S Offline
                  sootoo23
                  wrote on last edited by
                  #13

                  @jsulm
                  Yes, i have endless loop.
                  I’m using tow QTimers.

                  jsulmJ 1 Reply Last reply
                  0
                  • S sootoo23

                    @jsulm
                    Yes, i have endless loop.
                    I’m using tow QTimers.

                    jsulmJ Offline
                    jsulmJ Offline
                    jsulm
                    Lifetime Qt Champion
                    wrote on last edited by SGaist
                    #14

                    @sootoo23 Endless loops are a bad idea when using event driven frameworks like Qt...

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

                    S 2 Replies Last reply
                    1
                    • jsulmJ jsulm

                      @sootoo23 Endless loops are a bad idea when using event driven frameworks like Qt...

                      S Offline
                      S Offline
                      sootoo23
                      wrote on last edited by
                      #15

                      @jsulm
                      Instead of a regular endless loop,
                      Is it also a problem when using QTimer?

                      Also, how does the endless loop relate to the problem of not updating the text?

                      1 Reply Last reply
                      0
                      • jsulmJ jsulm

                        @sootoo23 Endless loops are a bad idea when using event driven frameworks like Qt...

                        S Offline
                        S Offline
                        sootoo23
                        wrote on last edited by
                        #16

                        @jsulm

                        I tried to remove the endless loop,
                        but The problem was not solved.

                        jsulmJ 1 Reply Last reply
                        0
                        • S sootoo23

                          @jsulm

                          I tried to remove the endless loop,
                          but The problem was not solved.

                          jsulmJ Offline
                          jsulmJ Offline
                          jsulm
                          Lifetime Qt Champion
                          wrote on last edited by
                          #17

                          @sootoo23 Endless loops block the Qt event loop. If this event loop is blocked no signals are emitted and no events are handled - the UI is not updated. I don't know what the problem with your code is as I don't have it.

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

                          1 Reply Last reply
                          2
                          • SGaistS Offline
                            SGaistS Offline
                            SGaist
                            Lifetime Qt Champion
                            wrote on last edited by
                            #18

                            Can you show the latest complete version of that part of your code ?

                            With only I removed something and it still doesn't work, there's no way to debug your problem.

                            Interested in AI ? www.idiap.ch
                            Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                            S 1 Reply Last reply
                            2
                            • SGaistS SGaist

                              Can you show the latest complete version of that part of your code ?

                              With only I removed something and it still doesn't work, there's no way to debug your problem.

                              S Offline
                              S Offline
                              sootoo23
                              wrote on last edited by sootoo23
                              #19

                              @SGaist

                              ------------mainwindow.cpp------------
                              MainWindow::MainWindow(QWidget *parent) :
                              QMainWindow(parent),
                              ui(new Ui::MainWindow)
                              {
                              ...
                              ...
                              #if (0)
                              //Removed endless loop timer
                              Hometimer = new QTimer(this);
                              connect(Hometimer, SIGNAL(timeout()),this,SLOT(HomeInfo_Update()));
                              Hometimer->start(1000);
                              #endif
                              }
                              void MainWindow::HomeInfo_Update()
                              {
                              ...
                              ...
                              ui->lb_HomeClk->setText(QString(TimeBuf));
                              ...
                              }

                              ------------menuQwidget.cpp------------
                              wnd_menu::wnd_menu(QWidget *parent) :
                              QWidget(parent),
                              ui(new Ui::wnd_menu)
                              {
                              ...
                              ...
                              #if (0)
                              //Removed endless loop timer
                              Menu_Timer = new QTimer;
                              connect(Menu_Timer, SIGNAL (timeout()), this, SLOT(MenuInfo_Update()));
                              Menu_Timer->start(1000);
                              Menu_Timer->blockSignals(true);
                              #endif
                              }

                              void wnd_menu::MenuInfo_Update()
                              {
                              ...
                              ...
                              ui->lb_MenuClk->setText(QString(TimeBuf));
                              ...
                              ...
                              }

                              jsulmJ K 2 Replies Last reply
                              0
                              • S sootoo23

                                @SGaist

                                ------------mainwindow.cpp------------
                                MainWindow::MainWindow(QWidget *parent) :
                                QMainWindow(parent),
                                ui(new Ui::MainWindow)
                                {
                                ...
                                ...
                                #if (0)
                                //Removed endless loop timer
                                Hometimer = new QTimer(this);
                                connect(Hometimer, SIGNAL(timeout()),this,SLOT(HomeInfo_Update()));
                                Hometimer->start(1000);
                                #endif
                                }
                                void MainWindow::HomeInfo_Update()
                                {
                                ...
                                ...
                                ui->lb_HomeClk->setText(QString(TimeBuf));
                                ...
                                }

                                ------------menuQwidget.cpp------------
                                wnd_menu::wnd_menu(QWidget *parent) :
                                QWidget(parent),
                                ui(new Ui::wnd_menu)
                                {
                                ...
                                ...
                                #if (0)
                                //Removed endless loop timer
                                Menu_Timer = new QTimer;
                                connect(Menu_Timer, SIGNAL (timeout()), this, SLOT(MenuInfo_Update()));
                                Menu_Timer->start(1000);
                                Menu_Timer->blockSignals(true);
                                #endif
                                }

                                void wnd_menu::MenuInfo_Update()
                                {
                                ...
                                ...
                                ui->lb_MenuClk->setText(QString(TimeBuf));
                                ...
                                ...
                                }

                                jsulmJ Offline
                                jsulmJ Offline
                                jsulm
                                Lifetime Qt Champion
                                wrote on last edited by
                                #20

                                @sootoo23

                                • Are the slots you connected to the timers called?
                                • Is TimeBuf set when these slots are called?

                                //Removed endless loop timer - this is not the kind of endless loop I mentioned. It is fine to use timers this way. The problem is somewhere else. You need to debug your app or upload the code to somewhere so we can take a look.

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

                                1 Reply Last reply
                                1
                                • S sootoo23

                                  @SGaist

                                  ------------mainwindow.cpp------------
                                  MainWindow::MainWindow(QWidget *parent) :
                                  QMainWindow(parent),
                                  ui(new Ui::MainWindow)
                                  {
                                  ...
                                  ...
                                  #if (0)
                                  //Removed endless loop timer
                                  Hometimer = new QTimer(this);
                                  connect(Hometimer, SIGNAL(timeout()),this,SLOT(HomeInfo_Update()));
                                  Hometimer->start(1000);
                                  #endif
                                  }
                                  void MainWindow::HomeInfo_Update()
                                  {
                                  ...
                                  ...
                                  ui->lb_HomeClk->setText(QString(TimeBuf));
                                  ...
                                  }

                                  ------------menuQwidget.cpp------------
                                  wnd_menu::wnd_menu(QWidget *parent) :
                                  QWidget(parent),
                                  ui(new Ui::wnd_menu)
                                  {
                                  ...
                                  ...
                                  #if (0)
                                  //Removed endless loop timer
                                  Menu_Timer = new QTimer;
                                  connect(Menu_Timer, SIGNAL (timeout()), this, SLOT(MenuInfo_Update()));
                                  Menu_Timer->start(1000);
                                  Menu_Timer->blockSignals(true);
                                  #endif
                                  }

                                  void wnd_menu::MenuInfo_Update()
                                  {
                                  ...
                                  ...
                                  ui->lb_MenuClk->setText(QString(TimeBuf));
                                  ...
                                  ...
                                  }

                                  K Offline
                                  K Offline
                                  kumararajas
                                  wrote on last edited by kumararajas
                                  #21

                                  @sootoo23 Both, setText functions does not get called at all. Hence, text is not displayed.

                                  And I don't know why 'blocksignals' function is used here.

                                  jsulmJ 1 Reply Last reply
                                  3
                                  • K Offline
                                    K Offline
                                    kumararajas
                                    wrote on last edited by
                                    #22
                                    This post is deleted!
                                    1 Reply Last reply
                                    0
                                    • K kumararajas

                                      @sootoo23 Both, setText functions does not get called at all. Hence, text is not displayed.

                                      And I don't know why 'blocksignals' function is used here.

                                      jsulmJ Offline
                                      jsulmJ Offline
                                      jsulm
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #23

                                      @kumararajas said in Text is not updated in qwidget.:

                                      And I don't know why 'blocksignals' function is used here.

                                      Wow, I didn't notice at all!

                                      @sootoo23 Why do you block the timer signals? This way you cannot expect the signals to be emitted and the slots called!

                                      Menu_Timer->blockSignals(true); // WHY?
                                      

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

                                      S 2 Replies Last reply
                                      4
                                      • jsulmJ jsulm

                                        @kumararajas said in Text is not updated in qwidget.:

                                        And I don't know why 'blocksignals' function is used here.

                                        Wow, I didn't notice at all!

                                        @sootoo23 Why do you block the timer signals? This way you cannot expect the signals to be emitted and the slots called!

                                        Menu_Timer->blockSignals(true); // WHY?
                                        
                                        S Offline
                                        S Offline
                                        sootoo23
                                        wrote on last edited by sootoo23
                                        #24

                                        @jsulm @kumararajas
                                        The main problem is not a block signal.
                                        The Timer is already blocked from use.

                                        Timer has nothing to do with the problem.

                                        The code that I uploaded is the code that removed the infinite loop (timer).

                                        Mainwindow.cpp -> menuQwidget->show();
                                        menuQwidget.cpp -> Dialog_Keypad->exec();

                                        ------------DialogKeypad.cpp------------
                                        my problem... not updated >>>>> LB_SetVal->setText(SetValue);

                                        1 Reply Last reply
                                        0
                                        • jsulmJ jsulm

                                          @kumararajas said in Text is not updated in qwidget.:

                                          And I don't know why 'blocksignals' function is used here.

                                          Wow, I didn't notice at all!

                                          @sootoo23 Why do you block the timer signals? This way you cannot expect the signals to be emitted and the slots called!

                                          Menu_Timer->blockSignals(true); // WHY?
                                          
                                          S Offline
                                          S Offline
                                          sootoo23
                                          wrote on last edited by sootoo23
                                          #25

                                          @jsulm @kumararajas
                                          ------------mainwindow.cpp------------
                                          MainWindow::MainWindow(QWidget *parent) :
                                          QMainWindow(parent),
                                          ui(new Ui::MainWindow)
                                          {
                                          ...
                                          ...
                                          #if (0)
                                          //Removed endless loop timer
                                          Hometimer = new QTimer(this);
                                          connect(Hometimer, SIGNAL(timeout()),this,SLOT(HomeInfo_Update()));
                                          Hometimer->start(1000);
                                          #endif
                                          }
                                          void MainWindow::HomeInfo_Update()
                                          {
                                          ...
                                          ...
                                          ui->lb_HomeClk->setText(QString(TimeBuf));
                                          ...
                                          }

                                          ------------menuQwidget.cpp------------
                                          wnd_menu::wnd_menu(QWidget *parent) :
                                          QWidget(parent),
                                          ui(new Ui::wnd_menu)
                                          {
                                          ...
                                          ...
                                          #if (0)
                                          //Removed endless loop timer
                                          Menu_Timer = new QTimer;
                                          connect(Menu_Timer, SIGNAL (timeout()), this, SLOT(MenuInfo_Update()));
                                          Menu_Timer->start(1000);
                                          Menu_Timer->blockSignals(true);
                                          #endif
                                          }

                                          void wnd_menu::MenuInfo_Update()
                                          {
                                          ...
                                          ...
                                          ui->lb_MenuClk->setText(QString(TimeBuf));
                                          ...
                                          ...
                                          }

                                          ------------DialogKeypad.cpp------------
                                          Dialog_Keypad::Dialog_Keypad(QWidget *parent) :
                                          QDialog(parent),
                                          ui(new Ui::Dialog_Keypad)
                                          {
                                          ui->setupUi(this);

                                          QString img_path = "/images/Keypad.jpg";
                                          QImage img(img_path);    
                                          QPixmap buf = QPixmap::fromImage(img);    
                                          QGraphicsScene* MenuScene = new QGraphicsScene;
                                          
                                          ui->KeypadFrame->setScene(MenuScene);
                                          MenuScene->addPixmap(buf);
                                          
                                          //text color setting
                                          QPalette* palette = new QPalette();
                                          palette->setColor(QPalette::WindowText,Qt::yellow);
                                          ui->lb_SettingValue->setPalette(*palette);	
                                          
                                          
                                          connect(ui->Keypad_Num0, SIGNAL(clicked()), &KeyPadMapper, SLOT(map()));
                                          connect(ui->Keypad_Num1, SIGNAL(clicked()), &KeyPadMapper, SLOT(map()));
                                          connect(ui->Keypad_Num2, SIGNAL(clicked()), &KeyPadMapper, SLOT(map()));
                                          connect(ui->Keypad_Num3, SIGNAL(clicked()), &KeyPadMapper, SLOT(map()));
                                          connect(ui->Keypad_Num4, SIGNAL(clicked()), &KeyPadMapper, SLOT(map()));
                                          connect(ui->Keypad_Num5, SIGNAL(clicked()), &KeyPadMapper, SLOT(map()));
                                          connect(ui->Keypad_Num6, SIGNAL(clicked()), &KeyPadMapper, SLOT(map()));
                                          connect(ui->Keypad_Num7, SIGNAL(clicked()), &KeyPadMapper, SLOT(map()));
                                          connect(ui->Keypad_Num8, SIGNAL(clicked()), &KeyPadMapper, SLOT(map()));
                                          connect(ui->Keypad_Num9, SIGNAL(clicked()), &KeyPadMapper, SLOT(map()));
                                          connect(ui->Keypad_Dot,  SIGNAL(clicked()), &KeyPadMapper, SLOT(map()));
                                          
                                          KeyPadMapper.setMapping(ui->Keypad_Num0, 0);
                                          KeyPadMapper.setMapping(ui->Keypad_Num1, 1);
                                          KeyPadMapper.setMapping(ui->Keypad_Num2, 2);
                                          KeyPadMapper.setMapping(ui->Keypad_Num3, 3);
                                          KeyPadMapper.setMapping(ui->Keypad_Num4, 4);
                                          KeyPadMapper.setMapping(ui->Keypad_Num5, 5);
                                          KeyPadMapper.setMapping(ui->Keypad_Num6, 6);
                                          KeyPadMapper.setMapping(ui->Keypad_Num7, 7);
                                          KeyPadMapper.setMapping(ui->Keypad_Num8, 8);
                                          KeyPadMapper.setMapping(ui->Keypad_Num9, 9);
                                          KeyPadMapper.setMapping(ui->Keypad_Dot, 100);
                                          
                                          connect(&KeyPadMapper, SIGNAL(mapped(int)), this, SLOT(SetKeypadData(int)));
                                          

                                          }

                                          void Dialog_Keypad::SetKeypadData(int val)
                                          {
                                          char keypadBuf[30] = {0,};
                                          QLabel* LB_SetVal;

                                          if(CurKeypadType == KEYPAD_NORMAL)
                                          	LB_SetVal = ui->lb_SettingValue;
                                          else if(CurKeypadType == KEYPAD_NETWORK)
                                          	LB_SetVal = ui->lb_NetSetVal;
                                          else if(CurKeypadType == KEYPAD_PASSWORD)
                                          	LB_SetVal = ui->lb_PWSetVal;
                                          else 
                                          	LB_SetVal = ui->lb_SettingValue;
                                          
                                          if(CurKeypadType == KEYPAD_PASSWORD)
                                          {
                                          	if(LB_SetVal->text().size() > 3)
                                          	{
                                          		printf("[%s] Password Length Over. :%s \n", __FUNCTION__, QByteArray(LB_SetVal->text().toLocal8Bit()).data());
                                          		return;
                                          	}
                                          	
                                          	SetValue = SetValue + QString::number(val);
                                          	sprintf((char *)keypadBuf, "%s%s", QByteArray(LB_SetVal->text().toLocal8Bit()).data(), "*");
                                          	LB_SetVal->setText(QString(keypadBuf));
                                          	return;
                                          }
                                          else if(CurKeypadType == KEYPAD_NETWORK)
                                          {
                                          	if(LB_SetVal->text().size() > 14)
                                          	{
                                          		printf("[%s] Network Setting Str Length Over.\n", __FUNCTION__);
                                          		return;
                                          	}
                                          	
                                          	if(val == 100) //dot.
                                          		sprintf((char *)keypadBuf, "%s%s", QByteArray(LB_SetVal->text().toLocal8Bit()).data(),".");
                                          	else if((LB_SetVal->text().size() == 3)
                                          			|| (LB_SetVal->text().size() == 7)
                                          			|| (LB_SetVal->text().size() == 11))
                                          		sprintf((char *)keypadBuf, "%s.%d", QByteArray(LB_SetVal->text().toLocal8Bit()).data(),val);
                                          	else
                                          		sprintf((char *)keypadBuf, "%s%d", QByteArray(LB_SetVal->text().toLocal8Bit()).data(),val);
                                          }
                                          else
                                          {		
                                          	if(val == 100) //dot.
                                          		sprintf((char *)keypadBuf, "%s%s", QByteArray(LB_SetVal->text().toLocal8Bit()).data(),".");
                                          	else
                                          		sprintf((char *)keypadBuf, "%s%d", QByteArray(LB_SetVal->text().toLocal8Bit()).data(),val);
                                          }
                                          
                                          SetValue = QString(keypadBuf);
                                           My Problem >> LB_SetVal->setText(SetValue);
                                          
                                          //qApp->processEvents();
                                          //qApp->sendPostedEvents();
                                          //qApp->processEvents(QEventLoop::ExcludeUserInput);
                                          //LB_SetVal->repaint();
                                          //LB_SetVal->parentWidget()->repaint();
                                          //LB_SetVal->update();
                                          //LB_SetVal->parentWidget()->update();
                                          
                                          printf("[%s] %s\n", __FUNCTION__, keypadBuf);
                                          

                                          }

                                          J.HilkJ 1 Reply Last reply
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