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how to automatically update GUI status

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  • J.HilkJ J.Hilk

    @Mijaz
    here's one way you can do it, using the signals @jsulm pointed you to

    MainWindow::MainWindow(QWidget *parent) :
        QMainWindow(parent),
        ui(new Ui::MainWindow)
    {
        ui->setupUi(this);
        connect(ui->lineEdit, &QLineEdit::textEdited, this, [=]()->void{
            QString str = ui->lineEdit->text();
            qDebug()<<"Input (HEX) = " << str;
            bool ok;
            int iVal = str.toInt(&ok,16);
            QString binnumber = str.setNum(iVal, 2);
            if(ok)
                ui->lineEdit_2->setText(binnumber);
            else
                ui->lineEdit_2->setText("Not a number");
            qDebug()<<"output in binary = " << binnumber;
        });
    }
    

    replace textEdited with editingFinished if you want to run this lambda(function) only when the user presses enter/return or the line edit looses focus

    MijazM Offline
    MijazM Offline
    Mijaz
    wrote on last edited by
    #10

    @J-Hilk
    This program correctly on Desktop. When I try to deply to my SDR Board then following error occures:
    1).
    /usr/local/Qt-4.8.7-arm/include/QtGui/qlineedit.h:196: error: ‘void QLineEdit::textEdited(const QString&)’ is protected
    void textEdited(const QString &);
    ^

    2).
    /home/ijaz/Qt_applications/update_automatically/mainwindow.cpp:11: error: within this context
    connect(ui->lineEdit, &QLineEdit::textEdited, this, =->void
    ^

    3).
    /home/ijaz/Qt_applications/update_automatically/mainwindow.cpp:23: warning: lambda expressions only available with -std=c++11 or -std=gnu++11 [enabled by default]
    });
    ^
    4).
    /home/ijaz/Qt_applications/update_automatically/mainwindow.cpp:23: error: no matching function for call to ‘MainWindow::connect(QLineEdit*&, void (QLineEdit::)(const QString&), MainWindow const, MainWindow::MainWindow(QWidget*)::__lambda0)’
    });
    ^

    jsulmJ J.HilkJ 2 Replies Last reply
    0
    • MijazM Mijaz

      @J-Hilk
      This program correctly on Desktop. When I try to deply to my SDR Board then following error occures:
      1).
      /usr/local/Qt-4.8.7-arm/include/QtGui/qlineedit.h:196: error: ‘void QLineEdit::textEdited(const QString&)’ is protected
      void textEdited(const QString &);
      ^

      2).
      /home/ijaz/Qt_applications/update_automatically/mainwindow.cpp:11: error: within this context
      connect(ui->lineEdit, &QLineEdit::textEdited, this, =->void
      ^

      3).
      /home/ijaz/Qt_applications/update_automatically/mainwindow.cpp:23: warning: lambda expressions only available with -std=c++11 or -std=gnu++11 [enabled by default]
      });
      ^
      4).
      /home/ijaz/Qt_applications/update_automatically/mainwindow.cpp:23: error: no matching function for call to ‘MainWindow::connect(QLineEdit*&, void (QLineEdit::)(const QString&), MainWindow const, MainWindow::MainWindow(QWidget*)::__lambda0)’
      });
      ^

      jsulmJ Offline
      jsulmJ Offline
      jsulm
      Lifetime Qt Champion
      wrote on last edited by jsulm
      #11

      @Mijaz said in how to automatically update GUI status:

      Qt-4.8.7-arm

      Is there a reason why you use Qt4?
      Also your compiler for the device does not support C++11.

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

      MijazM 1 Reply Last reply
      0
      • MijazM Mijaz

        @J-Hilk
        This program correctly on Desktop. When I try to deply to my SDR Board then following error occures:
        1).
        /usr/local/Qt-4.8.7-arm/include/QtGui/qlineedit.h:196: error: ‘void QLineEdit::textEdited(const QString&)’ is protected
        void textEdited(const QString &);
        ^

        2).
        /home/ijaz/Qt_applications/update_automatically/mainwindow.cpp:11: error: within this context
        connect(ui->lineEdit, &QLineEdit::textEdited, this, =->void
        ^

        3).
        /home/ijaz/Qt_applications/update_automatically/mainwindow.cpp:23: warning: lambda expressions only available with -std=c++11 or -std=gnu++11 [enabled by default]
        });
        ^
        4).
        /home/ijaz/Qt_applications/update_automatically/mainwindow.cpp:23: error: no matching function for call to ‘MainWindow::connect(QLineEdit*&, void (QLineEdit::)(const QString&), MainWindow const, MainWindow::MainWindow(QWidget*)::__lambda0)’
        });
        ^

        J.HilkJ Offline
        J.HilkJ Offline
        J.Hilk
        Moderators
        wrote on last edited by
        #12

        @Mijaz
        my example uses a lambda in the connect, that is only possible in Qt5 and newer. Not in QT 4

        But you should be able to move it in its own class function and connect it the old fashioned way


        Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


        Q: What's that?
        A: It's blue light.
        Q: What does it do?
        A: It turns blue.

        MijazM 1 Reply Last reply
        0
        • J.HilkJ J.Hilk

          @Mijaz
          my example uses a lambda in the connect, that is only possible in Qt5 and newer. Not in QT 4

          But you should be able to move it in its own class function and connect it the old fashioned way

          MijazM Offline
          MijazM Offline
          Mijaz
          wrote on last edited by
          #13

          @J-Hilk
          I have changed this code to the old version and it works fine. There are two cases I want to execute, cases are follows.

          case 1: Working correctly.

          MainWindow::MainWindow(QWidget *parent) :
          QMainWindow(parent),
          ui(new Ui::MainWindow)
          {
          ui->setupUi(this);
          connect(ui->lineEdit_input, SIGNAL(textEdited(QString)), this, SLOT(myFunction()));

          }

          void MainWindow::myFunction()
          {
          QString str = ui->lineEdit_input->text();
          qDebug()<<"Input (HEX) = " << str;
          ui->lineEdit_1->setText(str);
          bool ok1;
          qint64 iVal = str.toLongLong(&ok1,16);
          ui->lineEdit_2->setText(QString::number(iVal));
          QString binnumber = str.setNum(iVal, 2);
          ui->lineEdit_3->setText(binnumber);
          qDebug()<<"Convert to Int = " << QString::number(iVal);
          qDebug()<<"Convert to Binary = " << binnumber;
          qDebug()<<"size of string binnumber = " << binnumber.size();
          }
          Selection_032.png

          case 2: Not working correctly,

          MainWindow::MainWindow(QWidget *parent) :
          QMainWindow(parent),
          ui(new Ui::MainWindow)
          {
          ui->setupUi(this);
          connect(ui->lineEdit_input, SIGNAL(textEdited(QString)), this, SLOT(myFunction()));
          QProcess process;
          process.start("sudo devmem2 0x41210000");
          process.waitForFinished(-1); // will wait forever until finished
          QString stdout = process.readAllStandardOutput();
          qDebug()<<"Input (HEX) = " << stdout;
          QChar data[8] = { stdout[98], stdout[99], stdout[100], stdout[101], stdout[102], stdout[103], stdout[104],stdout[105]};
          QString str1(data, 8);
          qDebug()<<"Input (HEX) = " << str1;

          }

          void MainWindow::myFunction()
          {
          QString str = ui->lineEdit_input->setText(str1);
          qDebug()<<"Input (HEX) = " << str;
          ui->lineEdit_1->setText(str);
          bool ok1;
          qint64 iVal = str.toLongLong(&ok1,16);
          ui->lineEdit_2->setText(QString::number(iVal));
          QString binnumber = str.setNum(iVal, 2);
          ui->lineEdit_3->setText(binnumber);
          qDebug()<<"Convert to Int = " << QString::number(iVal);
          qDebug()<<"Convert to Binary = " << binnumber;
          qDebug()<<"size of string binnumber = " << binnumber.size();
          }

          Selection_033.png

          "QString str1" is unkown "void MainWindow::myFunction()"

          jsulmJ J.HilkJ 2 Replies Last reply
          0
          • MijazM Mijaz

            @J-Hilk
            I have changed this code to the old version and it works fine. There are two cases I want to execute, cases are follows.

            case 1: Working correctly.

            MainWindow::MainWindow(QWidget *parent) :
            QMainWindow(parent),
            ui(new Ui::MainWindow)
            {
            ui->setupUi(this);
            connect(ui->lineEdit_input, SIGNAL(textEdited(QString)), this, SLOT(myFunction()));

            }

            void MainWindow::myFunction()
            {
            QString str = ui->lineEdit_input->text();
            qDebug()<<"Input (HEX) = " << str;
            ui->lineEdit_1->setText(str);
            bool ok1;
            qint64 iVal = str.toLongLong(&ok1,16);
            ui->lineEdit_2->setText(QString::number(iVal));
            QString binnumber = str.setNum(iVal, 2);
            ui->lineEdit_3->setText(binnumber);
            qDebug()<<"Convert to Int = " << QString::number(iVal);
            qDebug()<<"Convert to Binary = " << binnumber;
            qDebug()<<"size of string binnumber = " << binnumber.size();
            }
            Selection_032.png

            case 2: Not working correctly,

            MainWindow::MainWindow(QWidget *parent) :
            QMainWindow(parent),
            ui(new Ui::MainWindow)
            {
            ui->setupUi(this);
            connect(ui->lineEdit_input, SIGNAL(textEdited(QString)), this, SLOT(myFunction()));
            QProcess process;
            process.start("sudo devmem2 0x41210000");
            process.waitForFinished(-1); // will wait forever until finished
            QString stdout = process.readAllStandardOutput();
            qDebug()<<"Input (HEX) = " << stdout;
            QChar data[8] = { stdout[98], stdout[99], stdout[100], stdout[101], stdout[102], stdout[103], stdout[104],stdout[105]};
            QString str1(data, 8);
            qDebug()<<"Input (HEX) = " << str1;

            }

            void MainWindow::myFunction()
            {
            QString str = ui->lineEdit_input->setText(str1);
            qDebug()<<"Input (HEX) = " << str;
            ui->lineEdit_1->setText(str);
            bool ok1;
            qint64 iVal = str.toLongLong(&ok1,16);
            ui->lineEdit_2->setText(QString::number(iVal));
            QString binnumber = str.setNum(iVal, 2);
            ui->lineEdit_3->setText(binnumber);
            qDebug()<<"Convert to Int = " << QString::number(iVal);
            qDebug()<<"Convert to Binary = " << binnumber;
            qDebug()<<"size of string binnumber = " << binnumber.size();
            }

            Selection_033.png

            "QString str1" is unkown "void MainWindow::myFunction()"

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

            @Mijaz said in how to automatically update GUI status:

            str1

            Where is it defined?
            The compiler actually tells you that it does not exist at that location...

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

            MijazM 1 Reply Last reply
            2
            • jsulmJ jsulm

              @Mijaz said in how to automatically update GUI status:

              Qt-4.8.7-arm

              Is there a reason why you use Qt4?
              Also your compiler for the device does not support C++11.

              MijazM Offline
              MijazM Offline
              Mijaz
              wrote on last edited by
              #15

              @jsulm

              I am using Qt4 because the errors occurred while cross-compilation of Qt5 to my Board.

              jsulmJ 1 Reply Last reply
              0
              • MijazM Mijaz

                @J-Hilk
                I have changed this code to the old version and it works fine. There are two cases I want to execute, cases are follows.

                case 1: Working correctly.

                MainWindow::MainWindow(QWidget *parent) :
                QMainWindow(parent),
                ui(new Ui::MainWindow)
                {
                ui->setupUi(this);
                connect(ui->lineEdit_input, SIGNAL(textEdited(QString)), this, SLOT(myFunction()));

                }

                void MainWindow::myFunction()
                {
                QString str = ui->lineEdit_input->text();
                qDebug()<<"Input (HEX) = " << str;
                ui->lineEdit_1->setText(str);
                bool ok1;
                qint64 iVal = str.toLongLong(&ok1,16);
                ui->lineEdit_2->setText(QString::number(iVal));
                QString binnumber = str.setNum(iVal, 2);
                ui->lineEdit_3->setText(binnumber);
                qDebug()<<"Convert to Int = " << QString::number(iVal);
                qDebug()<<"Convert to Binary = " << binnumber;
                qDebug()<<"size of string binnumber = " << binnumber.size();
                }
                Selection_032.png

                case 2: Not working correctly,

                MainWindow::MainWindow(QWidget *parent) :
                QMainWindow(parent),
                ui(new Ui::MainWindow)
                {
                ui->setupUi(this);
                connect(ui->lineEdit_input, SIGNAL(textEdited(QString)), this, SLOT(myFunction()));
                QProcess process;
                process.start("sudo devmem2 0x41210000");
                process.waitForFinished(-1); // will wait forever until finished
                QString stdout = process.readAllStandardOutput();
                qDebug()<<"Input (HEX) = " << stdout;
                QChar data[8] = { stdout[98], stdout[99], stdout[100], stdout[101], stdout[102], stdout[103], stdout[104],stdout[105]};
                QString str1(data, 8);
                qDebug()<<"Input (HEX) = " << str1;

                }

                void MainWindow::myFunction()
                {
                QString str = ui->lineEdit_input->setText(str1);
                qDebug()<<"Input (HEX) = " << str;
                ui->lineEdit_1->setText(str);
                bool ok1;
                qint64 iVal = str.toLongLong(&ok1,16);
                ui->lineEdit_2->setText(QString::number(iVal));
                QString binnumber = str.setNum(iVal, 2);
                ui->lineEdit_3->setText(binnumber);
                qDebug()<<"Convert to Int = " << QString::number(iVal);
                qDebug()<<"Convert to Binary = " << binnumber;
                qDebug()<<"size of string binnumber = " << binnumber.size();
                }

                Selection_033.png

                "QString str1" is unkown "void MainWindow::myFunction()"

                J.HilkJ Offline
                J.HilkJ Offline
                J.Hilk
                Moderators
                wrote on last edited by
                #16

                @Mijaz yes of course, str1 is a local variable inside your constructor function. myFunction()` has no knowledge of it.

                also, setText is a void function, it has no return value


                Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


                Q: What's that?
                A: It's blue light.
                Q: What does it do?
                A: It turns blue.

                1 Reply Last reply
                2
                • MijazM Mijaz

                  @jsulm

                  I am using Qt4 because the errors occurred while cross-compilation of Qt5 to my Board.

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

                  @Mijaz Keep in mind that Qt4 is reached its end of life already and is not supported anymore.

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

                  MijazM 1 Reply Last reply
                  0
                  • jsulmJ jsulm

                    @Mijaz said in how to automatically update GUI status:

                    str1

                    Where is it defined?
                    The compiler actually tells you that it does not exist at that location...

                    MijazM Offline
                    MijazM Offline
                    Mijaz
                    wrote on last edited by
                    #18

                    @jsulm
                    QString str1 is defined in MainWindow::MainWindow(QWidget *parent) :

                    jsulmJ MijazM 2 Replies Last reply
                    0
                    • MijazM Mijaz

                      @jsulm
                      QString str1 is defined in MainWindow::MainWindow(QWidget *parent) :

                      jsulmJ Offline
                      jsulmJ Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by
                      #19

                      @Mijaz said in how to automatically update GUI status:

                      QString str1 is defined in MainWindow::MainWindow(QWidget *parent) :

                      as local variable which only exists inside MainWindow::MainWindow(QWidget *parent)...

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

                      1 Reply Last reply
                      0
                      • MijazM Mijaz

                        @jsulm
                        QString str1 is defined in MainWindow::MainWindow(QWidget *parent) :

                        MijazM Offline
                        MijazM Offline
                        Mijaz
                        wrote on last edited by
                        #20

                        @Mijaz
                        now I have defined str1 in mainwindow.h
                        /////////////
                        public:
                        explicit MainWindow(QWidget *parent = 0);
                        ~MainWindow();
                        QString str1;

                        ///////////////////////
                        MainWindow::MainWindow(QWidget *parent) :
                        QMainWindow(parent),
                        ui(new Ui::MainWindow)
                        {
                        ui->setupUi(this);
                        connect(ui->lineEdit_input, SIGNAL(textEdited(QString)), this, SLOT(myFunction()));
                        QProcess process;
                        process.start("sudo devmem2 0x41210000");
                        process.waitForFinished(-1); // will wait forever until finished
                        QString stdout = process.readAllStandardOutput();
                        qDebug()<<"Input (HEX) = " << stdout;
                        QChar data[8] = { stdout[98], stdout[99], stdout[100], stdout[101], stdout[102], stdout[103], stdout[104],stdout[105]};
                        QString str11(data, 8);
                        qDebug()<<"local string = " << str11;
                        bool ok1;
                        str1= str11.toInt(&ok1,16);
                        qDebug()<<"Globle string = " << QString::number(str1);

                        }

                        void MainWindow::myFunction()
                        {
                        //QString str = ui->lineEdit_input->text();
                        QString str = str1;
                        qDebug()<<"Input (HEX) = " << str;
                        ui->lineEdit_1->setText(str);
                        bool ok1;
                        qint64 iVal = str.toLongLong(&ok1,16);
                        ui->lineEdit_2->setText(QString::number(iVal));
                        QString binnumber = str.setNum(iVal, 2);
                        ui->lineEdit_3->setText(binnumber);
                        qDebug()<<"Convert to Int = " << QString::number(iVal);
                        qDebug()<<"Convert to Binary = " << binnumber;
                        qDebug()<<"size of string binnumber = " << binnumber.size();
                        }
                        //////////////
                        error now:

                        /home/ijaz/QT_Final_project/my_push_button_update/mainwindow.cpp:22: error: no matching function for call to ‘QString::number(QString&)’
                        qDebug()<<"Globle string = " << QString::number(str1);
                        ^
                        Selection_034.png

                        JonBJ 1 Reply Last reply
                        0
                        • MijazM Mijaz

                          @Mijaz
                          now I have defined str1 in mainwindow.h
                          /////////////
                          public:
                          explicit MainWindow(QWidget *parent = 0);
                          ~MainWindow();
                          QString str1;

                          ///////////////////////
                          MainWindow::MainWindow(QWidget *parent) :
                          QMainWindow(parent),
                          ui(new Ui::MainWindow)
                          {
                          ui->setupUi(this);
                          connect(ui->lineEdit_input, SIGNAL(textEdited(QString)), this, SLOT(myFunction()));
                          QProcess process;
                          process.start("sudo devmem2 0x41210000");
                          process.waitForFinished(-1); // will wait forever until finished
                          QString stdout = process.readAllStandardOutput();
                          qDebug()<<"Input (HEX) = " << stdout;
                          QChar data[8] = { stdout[98], stdout[99], stdout[100], stdout[101], stdout[102], stdout[103], stdout[104],stdout[105]};
                          QString str11(data, 8);
                          qDebug()<<"local string = " << str11;
                          bool ok1;
                          str1= str11.toInt(&ok1,16);
                          qDebug()<<"Globle string = " << QString::number(str1);

                          }

                          void MainWindow::myFunction()
                          {
                          //QString str = ui->lineEdit_input->text();
                          QString str = str1;
                          qDebug()<<"Input (HEX) = " << str;
                          ui->lineEdit_1->setText(str);
                          bool ok1;
                          qint64 iVal = str.toLongLong(&ok1,16);
                          ui->lineEdit_2->setText(QString::number(iVal));
                          QString binnumber = str.setNum(iVal, 2);
                          ui->lineEdit_3->setText(binnumber);
                          qDebug()<<"Convert to Int = " << QString::number(iVal);
                          qDebug()<<"Convert to Binary = " << binnumber;
                          qDebug()<<"size of string binnumber = " << binnumber.size();
                          }
                          //////////////
                          error now:

                          /home/ijaz/QT_Final_project/my_push_button_update/mainwindow.cpp:22: error: no matching function for call to ‘QString::number(QString&)’
                          qDebug()<<"Globle string = " << QString::number(str1);
                          ^
                          Selection_034.png

                          JonBJ Offline
                          JonBJ Offline
                          JonB
                          wrote on last edited by
                          #21

                          @Mijaz
                          So look at the error message. It tells you precisely what is wrong, you don't need to ask. str1 is of type QString, and QString::number() takes a number and converts it to a string. Which you don't have or want....

                          MijazM 1 Reply Last reply
                          3
                          • JonBJ JonB

                            @Mijaz
                            So look at the error message. It tells you precisely what is wrong, you don't need to ask. str1 is of type QString, and QString::number() takes a number and converts it to a string. Which you don't have or want....

                            MijazM Offline
                            MijazM Offline
                            Mijaz
                            wrote on last edited by Mijaz
                            #22

                            @J-Hilk @JonB @jsulm
                            There are basically two different cases:
                            Case-1:
                            The user will give input in lineEdit_input and other things should update sharply according to the input. This case Working fine, I have attached code for this case.

                            Case-2:
                            In this case-2 user will not enter value but the value will come from QProcess function. If I will Execute this code without any loop it works fine but if QProcess output got changed then other things did not update according to QProcess.
                            Therefore I used a While loop to continually check the QProcess and update the required things. But, when I deploy this to the board and run the application it goes hang. The code for this case is also given.

                            Case-1
                            #include <QString>
                            #include <QProcess>
                            MainWindow::MainWindow(QWidget *parent) :
                            QMainWindow(parent),
                            ui(new Ui::MainWindow)
                            {
                            ui->setupUi(this);
                            connect(ui->lineEdit_input, SIGNAL(textEdited(QString)), this, SLOT(myFunction()));
                            }
                            void MainWindow::myFunction()
                            {
                            QString str1 = ui->lineEdit_input->text();
                            qDebug()<<"Input (HEX) = " << str1;
                            ui->lineEdit_1->setText(str1);
                            bool ok1;
                            qint64 iVal = str1.toLongLong(&ok1,16);
                            qDebug()<<"Convert to Int = " << QString::number(iVal);
                            ui->lineEdit_2->setText(QString::number(iVal));
                            QString binnumber = str1.setNum(iVal, 2);
                            ui->lineEdit_3->setText(binnumber);
                            qDebug()<<"Convert to Binary = " << binnumber;
                            qDebug()<<"size of string binnumber = " << binnumber.size();
                            }
                            Case-2
                            #include <QString>
                            #include <QProcess>
                            QString str1;
                            MainWindow::MainWindow(QWidget *parent) :
                            QMainWindow(parent),
                            ui(new Ui::MainWindow)
                            {
                            ui->setupUi(this);
                            while (1) {
                            QProcess process;
                            process.start("sudo devmem2 0x41210000");
                            process.waitForFinished(-1); // will wait forever until finished
                            QString stdout = process.readAllStandardOutput();
                            qDebug()<<"Input (HEX) = " << stdout;
                            QChar data[8] = { stdout[98], stdout[99], stdout[100], stdout[101], stdout[102], stdout[103], stdout[104],stdout[105]};
                            QString str11(data, 8);
                            qDebug()<<"Input (HEX) = " << str11;
                            str1= str11;
                            qDebug()<<"Globle = " << str1;
                            myFunction();
                            // for produce delay
                            for(int i=0;i<1000000;++i)
                            {
                            qDebug() << "Print i value" <<i;
                            }
                            }
                            }
                            void MainWindow::myFunction()
                            {
                            ui->lineEdit_input->setText(str1);
                            qDebug()<<"Input (HEX) = " << str1;
                            ui->lineEdit_1->setText(str1);
                            bool ok1;
                            qint64 iVal = str1.toLongLong(&ok1,16);
                            qDebug()<<"Convert to Int = " << QString::number(iVal);
                            ui->lineEdit_2->setText(QString::number(iVal));
                            QString binnumber = str1.setNum(iVal, 2);
                            ui->lineEdit_3->setText(binnumber);
                            qDebug()<<"Convert to Binary = " << binnumber;
                            qDebug()<<"size of string binnumber = " << binnumber.size();
                            }

                            JonBJ 2 Replies Last reply
                            0
                            • jsulmJ jsulm

                              @Mijaz Keep in mind that Qt4 is reached its end of life already and is not supported anymore.

                              MijazM Offline
                              MijazM Offline
                              Mijaz
                              wrote on last edited by Mijaz
                              #23

                              @jsulm
                              I have the Qt-5.9.5 version on my Desktop. I have tried to cross-compile this version at my board. I am facing an error at the ./configuration stage. Do you have any helpful resources for cross-compile?

                              I have followed the following websites. I have SDR ADRV9361 board instead of Raspberry.

                              https://wiki.qt.io/RaspberryPi2EGLFS
                              https://mechatronicsblog.com/cross-compile-and-deploy-qt-5-12-for-raspberry-pi/
                              https://forum.qt.io/topic/52546/tuto-build-qt-to-cross-compile-for-arm/2

                              the os-version of the board :
                              analog@analog:~$ cat /etc/os-release
                              NAME="Linaro"
                              VERSION="14.04"
                              ID=Linaro

                              the os-version of the Desktop
                              cat /etc/os-release
                              NAME="Ubuntu"
                              VERSION="18.04.2 LTS (Bionic Beaver)"
                              ID=ubuntu
                              ID_LIKE=debian
                              PRETTY_NAME="Ubuntu 18.04.2 LTS"
                              VERSION_ID="18.04"

                              Pablo J. RoginaP 1 Reply Last reply
                              -1
                              • MijazM Mijaz

                                @J-Hilk @JonB @jsulm
                                There are basically two different cases:
                                Case-1:
                                The user will give input in lineEdit_input and other things should update sharply according to the input. This case Working fine, I have attached code for this case.

                                Case-2:
                                In this case-2 user will not enter value but the value will come from QProcess function. If I will Execute this code without any loop it works fine but if QProcess output got changed then other things did not update according to QProcess.
                                Therefore I used a While loop to continually check the QProcess and update the required things. But, when I deploy this to the board and run the application it goes hang. The code for this case is also given.

                                Case-1
                                #include <QString>
                                #include <QProcess>
                                MainWindow::MainWindow(QWidget *parent) :
                                QMainWindow(parent),
                                ui(new Ui::MainWindow)
                                {
                                ui->setupUi(this);
                                connect(ui->lineEdit_input, SIGNAL(textEdited(QString)), this, SLOT(myFunction()));
                                }
                                void MainWindow::myFunction()
                                {
                                QString str1 = ui->lineEdit_input->text();
                                qDebug()<<"Input (HEX) = " << str1;
                                ui->lineEdit_1->setText(str1);
                                bool ok1;
                                qint64 iVal = str1.toLongLong(&ok1,16);
                                qDebug()<<"Convert to Int = " << QString::number(iVal);
                                ui->lineEdit_2->setText(QString::number(iVal));
                                QString binnumber = str1.setNum(iVal, 2);
                                ui->lineEdit_3->setText(binnumber);
                                qDebug()<<"Convert to Binary = " << binnumber;
                                qDebug()<<"size of string binnumber = " << binnumber.size();
                                }
                                Case-2
                                #include <QString>
                                #include <QProcess>
                                QString str1;
                                MainWindow::MainWindow(QWidget *parent) :
                                QMainWindow(parent),
                                ui(new Ui::MainWindow)
                                {
                                ui->setupUi(this);
                                while (1) {
                                QProcess process;
                                process.start("sudo devmem2 0x41210000");
                                process.waitForFinished(-1); // will wait forever until finished
                                QString stdout = process.readAllStandardOutput();
                                qDebug()<<"Input (HEX) = " << stdout;
                                QChar data[8] = { stdout[98], stdout[99], stdout[100], stdout[101], stdout[102], stdout[103], stdout[104],stdout[105]};
                                QString str11(data, 8);
                                qDebug()<<"Input (HEX) = " << str11;
                                str1= str11;
                                qDebug()<<"Globle = " << str1;
                                myFunction();
                                // for produce delay
                                for(int i=0;i<1000000;++i)
                                {
                                qDebug() << "Print i value" <<i;
                                }
                                }
                                }
                                void MainWindow::myFunction()
                                {
                                ui->lineEdit_input->setText(str1);
                                qDebug()<<"Input (HEX) = " << str1;
                                ui->lineEdit_1->setText(str1);
                                bool ok1;
                                qint64 iVal = str1.toLongLong(&ok1,16);
                                qDebug()<<"Convert to Int = " << QString::number(iVal);
                                ui->lineEdit_2->setText(QString::number(iVal));
                                QString binnumber = str1.setNum(iVal, 2);
                                ui->lineEdit_3->setText(binnumber);
                                qDebug()<<"Convert to Binary = " << binnumber;
                                qDebug()<<"size of string binnumber = " << binnumber.size();
                                }

                                JonBJ Offline
                                JonBJ Offline
                                JonB
                                wrote on last edited by JonB
                                #24

                                @Mijaz
                                But the post you made was to show a compilation error, and I pointed out what the message was and how it related to your code. What you have written since does not acknowledge that and has nothing to do with it. You seem to jump from one question to another without any explanation.

                                1 Reply Last reply
                                0
                                • MijazM Mijaz

                                  @J-Hilk @JonB @jsulm
                                  There are basically two different cases:
                                  Case-1:
                                  The user will give input in lineEdit_input and other things should update sharply according to the input. This case Working fine, I have attached code for this case.

                                  Case-2:
                                  In this case-2 user will not enter value but the value will come from QProcess function. If I will Execute this code without any loop it works fine but if QProcess output got changed then other things did not update according to QProcess.
                                  Therefore I used a While loop to continually check the QProcess and update the required things. But, when I deploy this to the board and run the application it goes hang. The code for this case is also given.

                                  Case-1
                                  #include <QString>
                                  #include <QProcess>
                                  MainWindow::MainWindow(QWidget *parent) :
                                  QMainWindow(parent),
                                  ui(new Ui::MainWindow)
                                  {
                                  ui->setupUi(this);
                                  connect(ui->lineEdit_input, SIGNAL(textEdited(QString)), this, SLOT(myFunction()));
                                  }
                                  void MainWindow::myFunction()
                                  {
                                  QString str1 = ui->lineEdit_input->text();
                                  qDebug()<<"Input (HEX) = " << str1;
                                  ui->lineEdit_1->setText(str1);
                                  bool ok1;
                                  qint64 iVal = str1.toLongLong(&ok1,16);
                                  qDebug()<<"Convert to Int = " << QString::number(iVal);
                                  ui->lineEdit_2->setText(QString::number(iVal));
                                  QString binnumber = str1.setNum(iVal, 2);
                                  ui->lineEdit_3->setText(binnumber);
                                  qDebug()<<"Convert to Binary = " << binnumber;
                                  qDebug()<<"size of string binnumber = " << binnumber.size();
                                  }
                                  Case-2
                                  #include <QString>
                                  #include <QProcess>
                                  QString str1;
                                  MainWindow::MainWindow(QWidget *parent) :
                                  QMainWindow(parent),
                                  ui(new Ui::MainWindow)
                                  {
                                  ui->setupUi(this);
                                  while (1) {
                                  QProcess process;
                                  process.start("sudo devmem2 0x41210000");
                                  process.waitForFinished(-1); // will wait forever until finished
                                  QString stdout = process.readAllStandardOutput();
                                  qDebug()<<"Input (HEX) = " << stdout;
                                  QChar data[8] = { stdout[98], stdout[99], stdout[100], stdout[101], stdout[102], stdout[103], stdout[104],stdout[105]};
                                  QString str11(data, 8);
                                  qDebug()<<"Input (HEX) = " << str11;
                                  str1= str11;
                                  qDebug()<<"Globle = " << str1;
                                  myFunction();
                                  // for produce delay
                                  for(int i=0;i<1000000;++i)
                                  {
                                  qDebug() << "Print i value" <<i;
                                  }
                                  }
                                  }
                                  void MainWindow::myFunction()
                                  {
                                  ui->lineEdit_input->setText(str1);
                                  qDebug()<<"Input (HEX) = " << str1;
                                  ui->lineEdit_1->setText(str1);
                                  bool ok1;
                                  qint64 iVal = str1.toLongLong(&ok1,16);
                                  qDebug()<<"Convert to Int = " << QString::number(iVal);
                                  ui->lineEdit_2->setText(QString::number(iVal));
                                  QString binnumber = str1.setNum(iVal, 2);
                                  ui->lineEdit_3->setText(binnumber);
                                  qDebug()<<"Convert to Binary = " << binnumber;
                                  qDebug()<<"size of string binnumber = " << binnumber.size();
                                  }

                                  JonBJ Offline
                                  JonBJ Offline
                                  JonB
                                  wrote on last edited by
                                  #25

                                  @Mijaz
                                  The code is hard to read because it's not indented and you do not use the forum post tools to display it is code. Please if you paste code at least use the </> icon button in the post's toolbar to mark as code, placing it inside 3 backtick markers.

                                  I do not claim to understand what you are saying Case-2 is trying to accomplish. But any code you use which has while (1) in MainWindow::MainWindow() is not going to be right. It will block, not allow the main Qt event loop to run, and "hang" the application as you say.

                                  You really need to move over to signals & slots, that's what is required in Qt program to avoid "hanging". Get rid of your for loop "to produce delay", it's quite the wrong way to do it (use a QTimer if you need a delay).

                                  1 Reply Last reply
                                  1
                                  • MijazM Mijaz

                                    @jsulm
                                    I have the Qt-5.9.5 version on my Desktop. I have tried to cross-compile this version at my board. I am facing an error at the ./configuration stage. Do you have any helpful resources for cross-compile?

                                    I have followed the following websites. I have SDR ADRV9361 board instead of Raspberry.

                                    https://wiki.qt.io/RaspberryPi2EGLFS
                                    https://mechatronicsblog.com/cross-compile-and-deploy-qt-5-12-for-raspberry-pi/
                                    https://forum.qt.io/topic/52546/tuto-build-qt-to-cross-compile-for-arm/2

                                    the os-version of the board :
                                    analog@analog:~$ cat /etc/os-release
                                    NAME="Linaro"
                                    VERSION="14.04"
                                    ID=Linaro

                                    the os-version of the Desktop
                                    cat /etc/os-release
                                    NAME="Ubuntu"
                                    VERSION="18.04.2 LTS (Bionic Beaver)"
                                    ID=ubuntu
                                    ID_LIKE=debian
                                    PRETTY_NAME="Ubuntu 18.04.2 LTS"
                                    VERSION_ID="18.04"

                                    Pablo J. RoginaP Offline
                                    Pablo J. RoginaP Offline
                                    Pablo J. Rogina
                                    wrote on last edited by
                                    #26

                                    @Mijaz said in how to automatically update GUI status:

                                    I have the Qt-5.9.5 version on my Desktop. I have tried to cross-compile this version at my board. I am facing an error at the ./configuration stage. Do you have any helpful resources for cross-compile?
                                    I have followed the following websites. I have SDR ADRV9361 board instead of Raspberry.

                                    Please do some favors to the community:

                                    1. Stop posting to a topic already marked as solved!
                                    2. Stop posting to a topic already marked as solved, with an issue completely unrelated to the original topic

                                    Working this way is only in your benefit, I'd rather say kinda selfish if you want, since I doubt somebody looking for help regarding cross-compilation will look at a topic titled "how to automatically update GUI status", right?

                                    Upvote the answer(s) that helped you solve the issue
                                    Use "Topic Tools" button to mark your post as Solved
                                    Add screenshots via postimage.org
                                    Don't ask support requests via chat/PM. Please use the forum so others can benefit from the solution in the future

                                    MijazM 1 Reply Last reply
                                    0
                                    • Pablo J. RoginaP Pablo J. Rogina

                                      @Mijaz said in how to automatically update GUI status:

                                      I have the Qt-5.9.5 version on my Desktop. I have tried to cross-compile this version at my board. I am facing an error at the ./configuration stage. Do you have any helpful resources for cross-compile?
                                      I have followed the following websites. I have SDR ADRV9361 board instead of Raspberry.

                                      Please do some favors to the community:

                                      1. Stop posting to a topic already marked as solved!
                                      2. Stop posting to a topic already marked as solved, with an issue completely unrelated to the original topic

                                      Working this way is only in your benefit, I'd rather say kinda selfish if you want, since I doubt somebody looking for help regarding cross-compilation will look at a topic titled "how to automatically update GUI status", right?

                                      MijazM Offline
                                      MijazM Offline
                                      Mijaz
                                      wrote on last edited by
                                      #27

                                      @Pablo-J-Rogina
                                      Ok sure I will aske every question as a new question.

                                      1 Reply Last reply
                                      0

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