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QLineEdit lostFocus problem

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  • EddyE Eddy

    did you
    #include <QApplication>

    TheCipo76T Offline
    TheCipo76T Offline
    TheCipo76
    wrote on last edited by TheCipo76
    #8

    @eddy said in QLineEdit lostFocus problem:

    #include <QApplication>

    you're right .. i forgot it

    but now i have this:

    duplicate symbol _Target in:
    fresatura.o
    mainwindow.o
    duplicate symbol _Target in:
    fresatura.o
    moc_fresatura.o
    ld: 2 duplicate symbols for architecture x86_64
    clang: error: linker command failed with exit code 1 (use -v to see invocation)
    make: *** [CNCMaster.app/Contents/MacOS/CNCMaster] Error 1
    14:06:25: The process "/usr/bin/make" exited with code 2.
    Error while building/deploying project CNCMaster (kit: Desktop Qt 5.13.0 clang 64bit)
    When executing step "Make"

    1 Reply Last reply
    0
    • EddyE Offline
      EddyE Offline
      Eddy
      wrote on last edited by Eddy
      #9

      search your project for "Target"
      the compiler tells you you have defined it twice

      EDIT: look in the pro file also

      Qt Certified Specialist
      www.edalsolutions.be

      TheCipo76T 1 Reply Last reply
      1
      • EddyE Eddy

        search your project for "Target"
        the compiler tells you you have defined it twice

        EDIT: look in the pro file also

        TheCipo76T Offline
        TheCipo76T Offline
        TheCipo76
        wrote on last edited by TheCipo76
        #10

        @eddy

        0_1565786150100_Schermata 2019-08-14 alle 14.30.39.png

        EDIT: can TARGET in pro file give duplicate??
        it's better change name??

        1 Reply Last reply
        0
        • EddyE Offline
          EddyE Offline
          Eddy
          wrote on last edited by
          #11

          I would not expect it.

          But anyway is it possible to upload a small compilable example. We're guessing all the time what could be wrong in your application.

          Qt Certified Specialist
          www.edalsolutions.be

          TheCipo76T 1 Reply Last reply
          2
          • EddyE Eddy

            I would not expect it.

            But anyway is it possible to upload a small compilable example. We're guessing all the time what could be wrong in your application.

            TheCipo76T Offline
            TheCipo76T Offline
            TheCipo76
            wrote on last edited by TheCipo76
            #12

            @eddy
            main.cpp

            #include "mainwindow.h"
            #include <QApplication>
            #include <QFont>
            
            
            
            int main(int argc, char *argv[])
            {
                QApplication a(argc, argv);
                MainWindow w;
                QFont V = QFont ("Verdana", 16);
                QApplication::setFont(V);
                w.showMaximized();
            
            
            
                return a.exec();
            }
            

            mainwindow.cpp

            #include "mainwindow.h"
            #include "ui_mainwindow.h"
            #include "fresatura.h"
            
            MainWindow::MainWindow(QWidget *parent) :
                QMainWindow(parent),
                ui(new Ui::MainWindow)
            {
                ui->setupUi(this);
            
            }
            
            MainWindow::~MainWindow()
            {
                delete ui;
            }
            
            void MainWindow::on_pushButton_Esci_clicked()
            {
                close();
            }
            
            void MainWindow::on_pushButton_Fresatura_clicked()
            {
                //FRESATURA
                fresatura Fresatura;
                Fresatura.setModal(true);
                Fresatura.exec();
            
            }
            
            

            fresatura.h

            #ifndef FRESATURA_H
            #define FRESATURA_H
            
            #include <QDialog>
            #include <QLineEdit>
            #include <QLabel>
            #include <QPushButton>
            #include <QWidget>
            #include <QApplication>
            
            QString Target;
            
            class MyLineEdit : public QLineEdit
            {
                Q_OBJECT
            public:
                MyLineEdit(QWidget *parent = nullptr) : QLineEdit(parent){}
            protected:
                void focusOutEvent(QFocusEvent *event)
                {
                   QLineEdit::focusOutEvent(event);
                   QWidget * widgetName = qApp->focusWidget();
                   Target = widgetName->objectName();
            
                    if(!hasAcceptableInput())
                    {
                        setFocus();
                    }
            
                }
            signals:
            };
            
            namespace Ui {
            class fresatura;
            }
            
            class fresatura : public QDialog
            {
                Q_OBJECT
            
            public:
                explicit fresatura(QWidget *parent = nullptr);
                ~fresatura();
            
            private slots:
            
            
            private:
                //Label
                QLabel *LFresatura;
                QLabel *LDiametro;
                QLabel *LVelTaglio;
                QLabel *LGiriMandrino;
                QLabel *LNDenti;
                QLabel *LAvDente;
                QLabel *LAvanzamento;
                //LineEdit
                //QLineEdit *Diametro;
                QLineEdit *VelTaglio;
                QLineEdit *GiriMandrino;
                QLineEdit *NDenti;
                QLineEdit *AvDente;
                QLineEdit *Avanzamento;
                //PushButton
                QPushButton *Zero;
                QPushButton *Uno;
                QPushButton *Due;
                QPushButton *Tre;
                QPushButton *Quattro;
                QPushButton *Cinque;
                QPushButton *Sei;
                QPushButton *Sette;
                QPushButton *Otto;
                QPushButton *Nove;
                //QPushButton *BS;
                //QPushButton *Punto;
            
                QPushButton *Esci;
            
                Ui::fresatura *ui;
            };
            
            #endif // FRESATURA_H
            

            fresatura.cpp

            #include "fresatura.h"
            #include "ui_fresatura.h"
            #include <QIntValidator>
            #include <QDoubleValidator>
            #include <QGridLayout>
            #include <QFont>
            #include <QMessageBox>
            
            
            fresatura::fresatura(QWidget *parent) :
                QDialog(parent),
                ui(new Ui::fresatura)
            {
                ui->setupUi(this);
            
                this->showMaximized();
                this->setFixedSize(1080, 1920);
                QFont V16 = QFont ("Verdana", 16);
                QFont VT = QFont ("Verdana", 34);
                this->setFont(V16);
            
                LFresatura = new QLabel(" F  R  E  S  A  T  U  R  A");
                LFresatura->setFont(VT);
            
                LDiametro = new QLabel("Diametro Fresa:");
                LVelTaglio = new QLabel("Velocità di Taglio:");
                LGiriMandrino = new QLabel("Giri Mandrino:");
                LNDenti = new QLabel("N. Denti Fresa:");
                LAvDente = new QLabel("Avanzam./Dente:");
                LAvanzamento = new QLabel("Avanzam. mm/min:");
            
                MyLineEdit *Diametro = new MyLineEdit();
                Diametro->setAlignment(Qt::AlignRight);
                Diametro->setValidator(new QIntValidator(1, 100, this));
            
                VelTaglio = new QLineEdit("");
                VelTaglio->setAlignment(Qt::AlignRight);
                VelTaglio->setValidator(new QIntValidator(1, 300, this));
            
                GiriMandrino = new QLineEdit("");
                GiriMandrino->setAlignment(Qt::AlignRight);
                GiriMandrino->setReadOnly(true);
            
                NDenti = new QLineEdit("");
                NDenti->setAlignment(Qt::AlignRight);
                NDenti->setValidator(new QIntValidator(1, 10, this));
            
                AvDente = new QLineEdit("");
                AvDente->setAlignment(Qt::AlignRight);
                AvDente->setValidator(new QDoubleValidator(0, 10, 2, this));
            
                Avanzamento = new QLineEdit("");
                Avanzamento->setAlignment(Qt::AlignRight);
                Avanzamento->setReadOnly(true);
            
                //KeyBoard
                Zero = new QPushButton;
                Zero->setText("0");
                Uno = new QPushButton;
                Uno->setText("1");
                Due = new QPushButton;
                Due->setText("2");
                Tre = new QPushButton;
                Tre->setText("3");
                Quattro = new QPushButton;
                Quattro->setText("4");
                Cinque = new QPushButton;
                Cinque->setText("5");
                Sei = new QPushButton;
                Sei->setText("6");
                Sette = new QPushButton;
                Sette->setText("7");
                Otto = new QPushButton;
                Otto->setText("8");
                Nove= new QPushButton;
                Nove->setText("9");
                QGridLayout *mainLayout = new QGridLayout;
                //mainLayout->setAlignment(Qt::AlignCenter);
                mainLayout->addWidget(LFresatura, 0, 0, 1, 2);
                mainLayout->setSizeConstraint(QLayout::SetFixedSize);
                mainLayout->addWidget(LDiametro, 1, 0);
                mainLayout->addWidget(Diametro, 1, 1);
                mainLayout->addWidget(LVelTaglio, 2, 0);
                mainLayout->addWidget(VelTaglio, 2, 1);
                mainLayout->addWidget(LGiriMandrino, 3, 0);
                mainLayout->addWidget(GiriMandrino, 3, 1);
                mainLayout->addWidget(LNDenti, 4, 0);
                mainLayout->addWidget(NDenti, 4, 1);
                mainLayout->addWidget(LAvDente, 5, 0);
                mainLayout->addWidget(AvDente, 5, 1);
                mainLayout->addWidget(LAvanzamento, 6, 0);
                mainLayout->addWidget(Avanzamento, 6, 1);
            
                mainLayout->addWidget(Uno, 7, 0);
                mainLayout->addWidget(Due, 7, 1);
                mainLayout->addWidget(Tre, 7, 2);
                mainLayout->addWidget(Quattro, 8, 0);
                mainLayout->addWidget(Cinque, 8, 1);
                mainLayout->addWidget(Sei, 8, 2);
                mainLayout->addWidget(Sette, 9, 0);
                mainLayout->addWidget(Otto, 9, 1);
                mainLayout->addWidget(Nove, 9, 2);
                this->setLayout(mainLayout);
            
            }
            
            
            
            fresatura::~fresatura()
            {
                delete ui;
            }
            
            

            Pro File:

            #-------------------------------------------------
            #
            # Project created by QtCreator 2019-08-08T13:35:11
            #
            #-------------------------------------------------
            
            QT       += core gui
            
            greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
            
            TARGET = CNCMaster
            TEMPLATE = app
            
            # The following define makes your compiler emit warnings if you use
            # any feature of Qt which has been marked as deprecated (the exact warnings
            # depend on your compiler). Please consult the documentation of the
            # deprecated API in order to know how to port your code away from it.
            DEFINES += QT_DEPRECATED_WARNINGS
            
            # You can also make your code fail to compile if you use deprecated APIs.
            # In order to do so, uncomment the following line.
            # You can also select to disable deprecated APIs only up to a certain version of Qt.
            #DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0
            
            CONFIG += c++11
            
            SOURCES += \
                    fresatura.cpp \
                    main.cpp \
                    mainwindow.cpp
            
            HEADERS += \
                    fresatura.h \
                    mainwindow.h
            
            FORMS += \
                    fresatura.ui \
                    mainwindow.ui
            
            CONFIG += mobility
            MOBILITY = 
            
            
            # Default rules for deployment.
            qnx: target.path = /tmp/$${TARGET}/bin
            else: unix:!android: target.path = /opt/$${TARGET}/bin
            !isEmpty(target.path): INSTALLS += target
            
            RESOURCES += \
                resource.qrc
            
            
            1 Reply Last reply
            0
            • EddyE Offline
              EddyE Offline
              Eddy
              wrote on last edited by Eddy
              #13

              at first glance I can see in your pro file:
              MOBILITY =

              Qt Certified Specialist
              www.edalsolutions.be

              TheCipo76T 1 Reply Last reply
              0
              • EddyE Eddy

                at first glance I can see in your pro file:
                MOBILITY =

                TheCipo76T Offline
                TheCipo76T Offline
                TheCipo76
                wrote on last edited by
                #14

                @eddy said in QLineEdit lostFocus problem:

                at first glance I can see in your pro file

                yes because i will try it as for Desktop and Android too

                1 Reply Last reply
                0
                • EddyE Offline
                  EddyE Offline
                  Eddy
                  wrote on last edited by
                  #15

                  You cannot put a line without putting something behind MOBILITY
                  like
                  MOBILITY += sensors
                  What is it you want to do here?

                  I recommend when looking at your code to make it work first on desktop before even thinking on using it on Android.
                  Comment that line for now and look in Qt Creator at all the lines with errors. Solve one at a time...you cannot let lines open or ignore warnings from the compiler.

                  Qt Certified Specialist
                  www.edalsolutions.be

                  TheCipo76T 1 Reply Last reply
                  1
                  • EddyE Eddy

                    You cannot put a line without putting something behind MOBILITY
                    like
                    MOBILITY += sensors
                    What is it you want to do here?

                    I recommend when looking at your code to make it work first on desktop before even thinking on using it on Android.
                    Comment that line for now and look in Qt Creator at all the lines with errors. Solve one at a time...you cannot let lines open or ignore warnings from the compiler.

                    TheCipo76T Offline
                    TheCipo76T Offline
                    TheCipo76
                    wrote on last edited by TheCipo76
                    #16

                    @eddy I've started to load it to my smartphone (Android) then i've decided to try before on my mac..

                    i haven't put this lines:

                    CONFIG += mobility
                    MOBILITY =
                    

                    in the pro file..

                    now i've comment it with #

                    the only errors i can see is in Compile Output:

                    duplicate symbol _Target in:
                    fresatura.o
                    mainwindow.o
                    duplicate symbol _Target in:
                    fresatura.o
                    moc_fresatura.o
                    ld: 2 duplicate symbols for architecture x86_64
                    clang: error: linker command failed with exit code 1 (use -v to see invocation)
                    make: *** [CNCMaster.app/Contents/MacOS/CNCMaster] Error 1
                    15:10:04: The process "/usr/bin/make" exited with code 2.
                    Error while building/deploying project CNCMaster (kit: Desktop Qt 5.13.0 clang 64bit)
                    When executing step "Make"
                    15:10:04: Elapsed time: 00:03.

                    i've searched in the project but i can't find duplicate

                    Pl45m4P 1 Reply Last reply
                    0
                    • TheCipo76T TheCipo76

                      @eddy I've started to load it to my smartphone (Android) then i've decided to try before on my mac..

                      i haven't put this lines:

                      CONFIG += mobility
                      MOBILITY =
                      

                      in the pro file..

                      now i've comment it with #

                      the only errors i can see is in Compile Output:

                      duplicate symbol _Target in:
                      fresatura.o
                      mainwindow.o
                      duplicate symbol _Target in:
                      fresatura.o
                      moc_fresatura.o
                      ld: 2 duplicate symbols for architecture x86_64
                      clang: error: linker command failed with exit code 1 (use -v to see invocation)
                      make: *** [CNCMaster.app/Contents/MacOS/CNCMaster] Error 1
                      15:10:04: The process "/usr/bin/make" exited with code 2.
                      Error while building/deploying project CNCMaster (kit: Desktop Qt 5.13.0 clang 64bit)
                      When executing step "Make"
                      15:10:04: Elapsed time: 00:03.

                      i've searched in the project but i can't find duplicate

                      Pl45m4P Offline
                      Pl45m4P Offline
                      Pl45m4
                      wrote on last edited by
                      #17

                      @thecipo76

                      It may cause trouble, because you define two QObject - derived classes in one header file. Put your custom LineEdit in a separate headerfile (and .cpp) and include it in your dialog. Then try to compile it again :)


                      If debugging is the process of removing software bugs, then programming must be the process of putting them in.

                      ~E. W. Dijkstra

                      TheCipo76T 1 Reply Last reply
                      3
                      • Pl45m4P Pl45m4

                        @thecipo76

                        It may cause trouble, because you define two QObject - derived classes in one header file. Put your custom LineEdit in a separate headerfile (and .cpp) and include it in your dialog. Then try to compile it again :)

                        TheCipo76T Offline
                        TheCipo76T Offline
                        TheCipo76
                        wrote on last edited by
                        #18

                        @pl45m4
                        i've definded it in a separate file

                        mylineedit.h

                        #ifndef MYLINEEDIT_H
                        #define MYLINEEDIT_H
                        
                        #include <QApplication>
                        #include <QLineEdit>
                        
                        extern QString Target;
                        
                        class MyLineEdit : public QLineEdit
                        {
                            Q_OBJECT
                        public:
                            MyLineEdit(QWidget *parent = nullptr) : QLineEdit(parent){}
                        protected:
                            void focusOutEvent(QFocusEvent *event)
                            {
                               QLineEdit::focusOutEvent(event);
                               QWidget * widgetName = qApp->focusWidget();
                               Target = widgetName->objectName();
                        
                                if(!hasAcceptableInput())
                                {
                                    setFocus();
                                }
                        
                            }
                        signals:
                        };
                        
                        #endif // MYLINEEDIT_H
                        
                        

                        and i've #included it in fresatura.cpp

                        #include "mylineedit.h"
                        

                        but no way..

                        Undefined symbols for architecture x86_64:
                        "_Target", referenced from:
                        MyLineEdit::focusOutEvent(QFocusEvent*) in moc_mylineedit.o
                        ld: symbol(s) not found for architecture x86_64
                        clang: error: linker command failed with exit code 1 (use -v to see invocation)
                        make: *** [CNCMaster.app/Contents/MacOS/CNCMaster] Error 1
                        15:32:58: The process "/usr/bin/make" exited with code 2.
                        Error while building/deploying project CNCMaster (kit: Desktop Qt 5.13.0 clang 64bit)
                        When executing step "Make"
                        15:32:58: Elapsed time: 00:02.

                        1 Reply Last reply
                        0
                        • mrjjM Offline
                          mrjjM Offline
                          mrjj
                          Lifetime Qt Champion
                          wrote on last edited by mrjj
                          #19

                          @thecipo76 said in QLineEdit lostFocus problem:
                          extern QString Target;

                          and then in the mylineedit.CPP file you also have

                          QString Target;

                          so its actually defined ?

                          TheCipo76T 1 Reply Last reply
                          3
                          • mrjjM mrjj

                            @thecipo76 said in QLineEdit lostFocus problem:
                            extern QString Target;

                            and then in the mylineedit.CPP file you also have

                            QString Target;

                            so its actually defined ?

                            TheCipo76T Offline
                            TheCipo76T Offline
                            TheCipo76
                            wrote on last edited by
                            #20

                            @mrjj ok i've defined it in .cpp file and works..
                            but i've lost Target value

                            1 Reply Last reply
                            1
                            • mrjjM Offline
                              mrjjM Offline
                              mrjj
                              Lifetime Qt Champion
                              wrote on last edited by
                              #21

                              Hi
                              Can you explain the original issue ?
                              If you click on lineEdit , then click on keyboard, then
                              lineedit loose its focus ?

                              TheCipo76T 1 Reply Last reply
                              0
                              • mrjjM mrjj

                                Hi
                                Can you explain the original issue ?
                                If you click on lineEdit , then click on keyboard, then
                                lineedit loose its focus ?

                                TheCipo76T Offline
                                TheCipo76T Offline
                                TheCipo76
                                wrote on last edited by
                                #22

                                @mrjj No, if i click on "1" pushbutton i have to read Target in order to know in wich mylineedit i have to insert "1".

                                Target is the mylineedit who lost focus

                                i don't know if it's clear

                                mrjjM 1 Reply Last reply
                                0
                                • TheCipo76T TheCipo76

                                  @mrjj No, if i click on "1" pushbutton i have to read Target in order to know in wich mylineedit i have to insert "1".

                                  Target is the mylineedit who lost focus

                                  i don't know if it's clear

                                  mrjjM Offline
                                  mrjjM Offline
                                  mrjj
                                  Lifetime Qt Champion
                                  wrote on last edited by
                                  #23

                                  @thecipo76
                                  well first of all the buttons should have NoFocus set so clicking them do not steal focus.
                                  There is no reason for it to lose focus unless you pop something else up first that takes focus.
                                  But in your case, its not keyboard that steal it but something else
                                  that takes focus while in the window ??

                                  TheCipo76T 1 Reply Last reply
                                  5
                                  • mrjjM mrjj

                                    @thecipo76
                                    well first of all the buttons should have NoFocus set so clicking them do not steal focus.
                                    There is no reason for it to lose focus unless you pop something else up first that takes focus.
                                    But in your case, its not keyboard that steal it but something else
                                    that takes focus while in the window ??

                                    TheCipo76T Offline
                                    TheCipo76T Offline
                                    TheCipo76
                                    wrote on last edited by TheCipo76
                                    #24

                                    @mrjj Ah.. with NoFocus setted i don't need to subclass QLineEdit
                                    and it's all more easy

                                    Thank you very much

                                    mrjjM 1 Reply Last reply
                                    1
                                    • TheCipo76T TheCipo76

                                      @mrjj Ah.. with NoFocus setted i don't need to subclass QLineEdit
                                      and it's all more easy

                                      Thank you very much

                                      mrjjM Offline
                                      mrjjM Offline
                                      mrjj
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #25

                                      @thecipo76
                                      Yep it helps a lot. :)
                                      I used qApp->focusWidget(); and sendEvent (key down / key up ) to post the keys to any widget that has keyboard focus and it works pretty well.

                                      1 Reply Last reply
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