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Pushbutton crashed.

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  • G Gutks

    @Pl45m4 said in Pushbutton crashed.:

    Thanks for responding and sorry for the delay.

    Pl45m4: "What is ui->pushButton() in your case?" - And I typed it wrong, thanks for correcting. ui->pushButton1.

    CustomPushButton.cpp, I tried to use macro const Q_Q(QAbstractButton),
    error: use of undeclared identifier 'q_func'.

    Not being able to access the emitPressed() and emitRelease(), class scope QAbstractButton.

    So my mousePressEvent and mouseReleaseEvent, stayed like this:
    customushbutton.cpp

    #include "custompushbutton.h"
    
    CustomPushButton::CustomPushButton(QWidget *parent){}
    void CustomPushButton::mousePressEvent(QMouseEvent *e){
        QAbstractButton *p;
        if(e->button()==Qt::LeftButton){p->click();emit pressed();}
        else{if(e->button()==Qt::RightButton){p->click();emit pressed();}else{e->ignore();return;}}
    }
    
    void CustomPushButton::mouseReleaseEvent(QMouseEvent *e){
        QAbstractButton *p;
        //Q_Q(QAbstractButton);
        if(e->button()==Qt::LeftButton){p->click();emit pressed();}
        else{if(e->button()==Qt::RightButton){p->click();emit pressed();}else{e->ignore();return;}}
    }
    

    test.cpp

    #include "test.h"
    #include "ui_test.h"
    #include "QMouseEvent"
    
    int value1= 0;
    int value2= 0;
    int value3= 0;
    int value4= 0;
    
    Test::Test(QWidget *parent) : QMainWindow(parent) , ui(new Ui::Test){
        ui->setupUi(this);
        ui->lineEdit1->setEnabled(false);
        ui->lineEdit2->setEnabled(false);
    
        connect(ui->button1, SIGNAL(leftClicked()) , this, SLOT(btnLeftClicked()))   ;
        connect(ui->button1, SIGNAL(rightClicked()), this, SLOT (btnRightClecked())) ;
    
        connect(ui->button2, SIGNAL(leftClicked()) , this, SLOT(btnLeftClicked()))   ;
        connect(ui->button2, SIGNAL(rightClicked()), this, SLOT(btnRightClicked()))  ;
    }
    

    QObject::connect: No such signal QPushButton::leftClicked()
    The connect and increment should be inside the on_button_clicked()?

    Yes, I put it as global, to facilitate the test. If I did it as a member of the class (seters and geters),

    I would have work to get the value of the line edit and convert string to number, and so do the increment
    and decrement.

    Pl45m4P Offline
    Pl45m4P Offline
    Pl45m4
    wrote on last edited by Pl45m4
    #6

    @Gutks said in Pushbutton crashed.:

    Not being able to access the emitPressed() and emitRelease(), class scope QAbstractButton.

    Why not? Your own pushbutton class inherits QPushbutton and you have added some signals on your own... Just emit these.
    (emit pressed() is the wrong signal after all. You named you signals in your button class differenta and these are the ones, you need to use inside your mouse event)

    And again my question :)
    Where do you create (new) your button instances button1 and button2?
    ui->button1 only works, if you've created your button with QtDesigner (or if they are part of your ui_classname.h at least).

    Edit:

    Do you make use of widget promotion? If yes, it may work like this, but if you don't, you'll need to instantiate your buttons first, in order to connect something to them.

    @Gutks said in Pushbutton crashed.:

    QObject::connect: No such signal QPushButton::leftClicked()

    This indicates, that your ui->button1 is currently not your custom button. I would say, these are still pointers to your basic QPushButtons.
    Read about "Promoting Widgets in Qt" (Link) or create your CustomPushbuttons by code and add them to you layout manually.

    Your QAbstractButton *p inside your mouseEvents also does nothing and is not necessary. What do you expect from doing this? :)

    @Gutks said in Pushbutton crashed.:

    I would have work to get the value of the line edit and convert string to number, and so do the increment
    and decrement.

    No, you dont. Only if you want to access these values from "outside". If you use them only their own class, you dont need getter / setter. In addition, you could make use of signals & slots to change the values, but if these are just counters, you dont even need to do that.


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

    ~E. W. Dijkstra

    G 1 Reply Last reply
    1
    • Pl45m4P Pl45m4

      @Gutks said in Pushbutton crashed.:

      Not being able to access the emitPressed() and emitRelease(), class scope QAbstractButton.

      Why not? Your own pushbutton class inherits QPushbutton and you have added some signals on your own... Just emit these.
      (emit pressed() is the wrong signal after all. You named you signals in your button class differenta and these are the ones, you need to use inside your mouse event)

      And again my question :)
      Where do you create (new) your button instances button1 and button2?
      ui->button1 only works, if you've created your button with QtDesigner (or if they are part of your ui_classname.h at least).

      Edit:

      Do you make use of widget promotion? If yes, it may work like this, but if you don't, you'll need to instantiate your buttons first, in order to connect something to them.

      @Gutks said in Pushbutton crashed.:

      QObject::connect: No such signal QPushButton::leftClicked()

      This indicates, that your ui->button1 is currently not your custom button. I would say, these are still pointers to your basic QPushButtons.
      Read about "Promoting Widgets in Qt" (Link) or create your CustomPushbuttons by code and add them to you layout manually.

      Your QAbstractButton *p inside your mouseEvents also does nothing and is not necessary. What do you expect from doing this? :)

      @Gutks said in Pushbutton crashed.:

      I would have work to get the value of the line edit and convert string to number, and so do the increment
      and decrement.

      No, you dont. Only if you want to access these values from "outside". If you use them only their own class, you dont need getter / setter. In addition, you could make use of signals & slots to change the values, but if these are just counters, you dont even need to do that.

      G Offline
      G Offline
      Gutks
      wrote on last edited by
      #7

      @Pl45m4

      NameProjet= Test;
      classe1= customPushButton.h ; customPushButton;
      Classe2= test.h ; test.cpp = ( Widget, ui->classe)
      other= main.cpp;

      I tried to use this logic similar to the previous tutorial, however, Macro ( Q_Q() ),
      it is not stated, when I try to instantiate q->emitPressed(). return error: use of undeclared identifier 'q_func';

      I tried to change the 'Q' for 'D' ( Q_D), equal to the situation below, returns another.
      error: cannot initialize a variable of type 'QAbstractButtonPrivate *const' with an rvalue of type 'QPushButtonPrivate'
      Q_D(Class)

      void QAbstractButton::mousePressEvent(QMouseEvent *e){
          Q_D(QAbstractButton);
          if (e->button() != Qt::LeftButton) {
              e->ignore();
              return;
          }
          if (hitButton(e->pos())) {
              setDown(true);
              d->pressed = true;
              repaint();
              d->emitPressed();
              e->accept();
          } else {
              e->ignore();
          }
      }
      

      Ok, I'm going to make the right sign and study the custom widgets with Qt Designer. Thank you for the patience, using google translation . I return with possible results or errors.

      JonBJ 1 Reply Last reply
      0
      • G Gutks

        @Pl45m4

        NameProjet= Test;
        classe1= customPushButton.h ; customPushButton;
        Classe2= test.h ; test.cpp = ( Widget, ui->classe)
        other= main.cpp;

        I tried to use this logic similar to the previous tutorial, however, Macro ( Q_Q() ),
        it is not stated, when I try to instantiate q->emitPressed(). return error: use of undeclared identifier 'q_func';

        I tried to change the 'Q' for 'D' ( Q_D), equal to the situation below, returns another.
        error: cannot initialize a variable of type 'QAbstractButtonPrivate *const' with an rvalue of type 'QPushButtonPrivate'
        Q_D(Class)

        void QAbstractButton::mousePressEvent(QMouseEvent *e){
            Q_D(QAbstractButton);
            if (e->button() != Qt::LeftButton) {
                e->ignore();
                return;
            }
            if (hitButton(e->pos())) {
                setDown(true);
                d->pressed = true;
                repaint();
                d->emitPressed();
                e->accept();
            } else {
                e->ignore();
            }
        }
        

        Ok, I'm going to make the right sign and study the custom widgets with Qt Designer. Thank you for the patience, using google translation . I return with possible results or errors.

        JonBJ Offline
        JonBJ Offline
        JonB
        wrote on last edited by JonB
        #8

        @Gutks
        Especially if you are a beginner, why are you trying to use macros like Q_D() and Q_Q() at all? So far as I know they are for internal Qt code. I have never used them in any user code I have written, why do you think you need them?

        G 1 Reply Last reply
        3
        • JonBJ JonB

          @Gutks
          Especially if you are a beginner, why are you trying to use macros like Q_D() and Q_Q() at all? So far as I know they are for internal Qt code. I have never used them in any user code I have written, why do you think you need them?

          G Offline
          G Offline
          Gutks
          wrote on last edited by Gutks
          #9

          @JonB In order to instantiate: emitPressed(); emitRelease(); equal example
          of the QAbstractButton class.

          Pablo J. RoginaP JonBJ 2 Replies Last reply
          0
          • G Gutks

            @JonB In order to instantiate: emitPressed(); emitRelease(); equal example
            of the QAbstractButton class.

            Pablo J. RoginaP Offline
            Pablo J. RoginaP Offline
            Pablo J. Rogina
            wrote on last edited by
            #10

            @Gutks said in Pushbutton crashed.:

            instantiate: emitPressed(); emitRelease();

            Mmm, strange that you need to "instantiate" what seems to be signals...

            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

            1 Reply Last reply
            2
            • G Gutks

              @JonB In order to instantiate: emitPressed(); emitRelease(); equal example
              of the QAbstractButton class.

              JonBJ Offline
              JonBJ Offline
              JonB
              wrote on last edited by JonB
              #11

              @Gutks
              Yes, but why are you doing so, given that emitPressed() is not documented and private to the innards of QAbstractButton? Which is why you are running into the compilation errors.... My question is: why are trying to do anything like this? The fact that it's in QAbstractButtonPrivate should give you a clue.

              G 1 Reply Last reply
              1
              • JonBJ JonB

                @Gutks
                Yes, but why are you doing so, given that emitPressed() is not documented and private to the innards of QAbstractButton? Which is why you are running into the compilation errors.... My question is: why are trying to do anything like this? The fact that it's in QAbstractButtonPrivate should give you a clue.

                G Offline
                G Offline
                Gutks
                wrote on last edited by
                #12

                @JonB

                The implementation of this function is accessing Q_D, since I am re-implementing it, I thought I could do the same.

                void QAbstractButton::mousePressEvent(QMouseEvent *e)
                

                I will study the qt designer, to try to solve, otherwise, I will create an Auxiliary button to remove in the edit line. I think it's simpler than using events

                JonBJ 1 Reply Last reply
                0
                • G Gutks

                  @JonB

                  The implementation of this function is accessing Q_D, since I am re-implementing it, I thought I could do the same.

                  void QAbstractButton::mousePressEvent(QMouseEvent *e)
                  

                  I will study the qt designer, to try to solve, otherwise, I will create an Auxiliary button to remove in the edit line. I think it's simpler than using events

                  JonBJ Offline
                  JonBJ Offline
                  JonB
                  wrote on last edited by
                  #13

                  @Gutks
                  But why are you "re-implementing" it at all? Usually a user class sub-classes, not re-implements. Re-implementing is fraught, e.g. what happens if the internals change over time. Since you say "I'm a beginner" I cannot see why you would want to do such a thing, when 99.9% of other users do not.

                  I keep saying the same thing, so I'll leave it to you now.

                  G 1 Reply Last reply
                  2
                  • JonBJ JonB

                    @Gutks
                    But why are you "re-implementing" it at all? Usually a user class sub-classes, not re-implements. Re-implementing is fraught, e.g. what happens if the internals change over time. Since you say "I'm a beginner" I cannot see why you would want to do such a thing, when 99.9% of other users do not.

                    I keep saying the same thing, so I'll leave it to you now.

                    G Offline
                    G Offline
                    Gutks
                    wrote on last edited by
                    #14

                    @JonB
                    Okay, thanks for trying to help. I will search for a solution to my problem.

                    Pl45m4P JonBJ Pablo J. RoginaP 5 Replies Last reply
                    0
                    • G Gutks

                      @JonB
                      Okay, thanks for trying to help. I will search for a solution to my problem.

                      Pl45m4P Offline
                      Pl45m4P Offline
                      Pl45m4
                      wrote on last edited by
                      #15

                      @Gutks

                      I already gave you an almost step by step manual how to solve your problem... You dont need Q_Q or reimplement any signals.


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

                      ~E. W. Dijkstra

                      1 Reply Last reply
                      2
                      • G Gutks

                        @JonB
                        Okay, thanks for trying to help. I will search for a solution to my problem.

                        JonBJ Offline
                        JonBJ Offline
                        JonB
                        wrote on last edited by
                        #16

                        @Gutks
                        Both @Pl45m4 & I are trying to say you don't need to go down the route you are on....

                        1 Reply Last reply
                        1
                        • G Gutks

                          @JonB
                          Okay, thanks for trying to help. I will search for a solution to my problem.

                          Pablo J. RoginaP Offline
                          Pablo J. RoginaP Offline
                          Pablo J. Rogina
                          wrote on last edited by
                          #17

                          @Gutks said in Pushbutton crashed.:

                          if(p->button()==Qt::LeftButton){ui->lineEdit1->setText(QString::number(value1++));}
                          
                          else{if(p->button()==Qt::RightButton){ui->lineEdit1->setText(QString::number(value1--));}
                          

                          From your requirements it's apparent you need a custom QPushButton that extends existing one by adding just the rightclicked() signal, and nothing else. So you'll have both signals (existing left click) and new one (right click) to connect as you wish.

                          Please take a look at this SO question & answers.

                          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

                          1 Reply Last reply
                          2
                          • G Gutks

                            @JonB
                            Okay, thanks for trying to help. I will search for a solution to my problem.

                            JonBJ Offline
                            JonBJ Offline
                            JonB
                            wrote on last edited by JonB
                            #18

                            @Gutks
                            If what @Pablo-J-Rogina has discerned is correct --- you just want a left-/right-click to increment/decrement a number in a QLineEdit, is that right? --- then you would be better just using a QSpinBox, which is for entering numbers, and you wouldn't have any of this.....

                            Pablo J. RoginaP 1 Reply Last reply
                            1
                            • JonBJ JonB

                              @Gutks
                              If what @Pablo-J-Rogina has discerned is correct --- you just want a left-/right-click to increment/decrement a number in a QLineEdit, is that right? --- then you would be better just using a QSpinBox, which is for entering numbers, and you wouldn't have any of this.....

                              Pablo J. RoginaP Offline
                              Pablo J. RoginaP Offline
                              Pablo J. Rogina
                              wrote on last edited by
                              #19

                              @JonB said in Pushbutton crashed.:

                              then you would be better just using a QSpinBox,

                              I think the goal here is the rightclicked() signal, what you connect that to is not relevant at this point

                              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

                              JonBJ 1 Reply Last reply
                              3
                              • Pablo J. RoginaP Pablo J. Rogina

                                @JonB said in Pushbutton crashed.:

                                then you would be better just using a QSpinBox,

                                I think the goal here is the rightclicked() signal, what you connect that to is not relevant at this point

                                JonBJ Offline
                                JonBJ Offline
                                JonB
                                wrote on last edited by JonB
                                #20

                                @Pablo-J-Rogina
                                Oh, I see. You may be right. Or it just might turn out the user was going to use a left-/-right-click on a button to inc/dec a number, you never know... :)

                                On a different tone, it's "unusual" to have the user right-click on a button. Possible, but possibly not intuitive. A "rocker" pushbutton (click at left/right for different behaviour, but with left mouse) might be another possibility.

                                Pl45m4P 1 Reply Last reply
                                1
                                • G Gutks

                                  @JonB
                                  Okay, thanks for trying to help. I will search for a solution to my problem.

                                  Pl45m4P Offline
                                  Pl45m4P Offline
                                  Pl45m4
                                  wrote on last edited by Pl45m4
                                  #21

                                  @Gutks

                                  Button.h

                                  #ifndef LR_CLICKBUTTON_H
                                  #define LR_CLICKBUTTON_H
                                  
                                  #include <QPushButton>
                                  
                                  class LR_ClickButton: public QPushButton
                                  {
                                      Q_OBJECT
                                  public:
                                  
                                      LR_ClickButton(QWidget *parent = nullptr);
                                  
                                  
                                  protected:
                                     void	mousePressEvent(QMouseEvent *e) override;
                                     void mouseReleaseEvent(QMouseEvent *e) override;
                                  
                                  signals:
                                      // Not needed, since one signal which sends MouseEvent to get handled in slot
                                      //void leftClicked();
                                      //void rightClicked();
                                  
                                      void myClicked(QMouseEvent *e);
                                  };
                                  
                                  #endif // LR_CLICKBUTTON_H
                                  

                                  Button.cpp

                                  #include "lr_clickbutton.h"
                                  #include <QMouseEvent>
                                  #include <QDebug>
                                  LR_ClickButton::LR_ClickButton(QWidget *parent):
                                      QPushButton(parent)
                                  {
                                  
                                  }
                                  
                                  void LR_ClickButton::mousePressEvent(QMouseEvent *e)
                                  {
                                      QPushButton::mousePressEvent(e);
                                  }
                                  
                                  void LR_ClickButton::mouseReleaseEvent(QMouseEvent *e)
                                  {
                                      if(e->button() == Qt::LeftButton)
                                      {
                                          qDebug() << "Left";
                                          emit myClicked(e);
                                      }
                                      else if (e->button() == Qt::RightButton) {
                                  
                                          qDebug() << "Right";
                                          emit myClicked(e);
                                  
                                      }
                                          QPushButton::mouseReleaseEvent(e);
                                  }
                                  

                                  MainWindow.h

                                  public slots:
                                      void myButtonClicked(QMouseEvent *e);
                                  

                                  MainWindow.cpp

                                  // #########  C'TOR  #####################
                                      LR_ClickButton *button1 = new LR_ClickButton(this);
                                  
                                      centralWidget()->layout()->addWidget(button1);
                                  
                                      connect(button1, &LR_ClickButton::myClicked, this, &MainWindow::myButtonClicked);
                                  
                                  // ######################################
                                  
                                  
                                  void MainWindow::myButtonClicked(QMouseEvent *e)
                                  {
                                      if(e->button() == Qt::LeftButton)
                                      {
                                          // Of course you can put anything you want here
                                          int val = ui->spinBox->value();
                                          ui->spinBox->setValue(val + 1);
                                      }
                                      else if (e->button() == Qt::RightButton) {
                                  
                                          // or here
                                          int val = ui->spinBox->value();
                                          ui->spinBox->setValue(val - 1);
                                      }
                                  }
                                  
                                  
                                  

                                  Wasn't that hard, right? :)

                                  Result:

                                  3 left-clicks increase value by 3.
                                  Bildschirmfoto vom 2020-08-19 15-13-02.png

                                  2 right-clicks decrease value by 2 again.
                                  Bildschirmfoto vom 2020-08-19 15-13-33.png


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

                                  ~E. W. Dijkstra

                                  1 Reply Last reply
                                  1
                                  • JonBJ JonB

                                    @Pablo-J-Rogina
                                    Oh, I see. You may be right. Or it just might turn out the user was going to use a left-/-right-click on a button to inc/dec a number, you never know... :)

                                    On a different tone, it's "unusual" to have the user right-click on a button. Possible, but possibly not intuitive. A "rocker" pushbutton (click at left/right for different behaviour, but with left mouse) might be another possibility.

                                    Pl45m4P Offline
                                    Pl45m4P Offline
                                    Pl45m4
                                    wrote on last edited by
                                    #22

                                    @JonB said in Pushbutton crashed.:

                                    On a different tone, it's "unusual" to have the user right-click on a button. Possible, but possibly not intuitive

                                    Might not be the most intuitive solution but this is actually used a lot in games (with a hint to this behavior ofc)


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

                                    ~E. W. Dijkstra

                                    JonBJ 1 Reply Last reply
                                    1
                                    • Pl45m4P Pl45m4

                                      @JonB said in Pushbutton crashed.:

                                      On a different tone, it's "unusual" to have the user right-click on a button. Possible, but possibly not intuitive

                                      Might not be the most intuitive solution but this is actually used a lot in games (with a hint to this behavior ofc)

                                      JonBJ Offline
                                      JonBJ Offline
                                      JonB
                                      wrote on last edited by
                                      #23

                                      @Pl45m4
                                      Point taken! Not in any of the games I play that I can think of, though most of mine are 2D turn-based from the last millennium... ;-)

                                      1 Reply Last reply
                                      2
                                      • G Offline
                                        G Offline
                                        Gutks
                                        wrote on last edited by Gutks
                                        #24

                                        @Christian-Ehrlicher @Pl45m4 @JonB @Pablo-J-Rogina

                                        Thank you very much, you don't know how it helped me. Otherwise, I would have to create an internal storage system for each button between the tabs and remove it when editing the line.

                                        Yes, and a tool I am creating to help the 1 game community. How does it activate as resolved?
                                        Captura de tela de 2020-08-19 08-05-11.png

                                        JonBJ 1 Reply Last reply
                                        1
                                        • G Gutks

                                          @Christian-Ehrlicher @Pl45m4 @JonB @Pablo-J-Rogina

                                          Thank you very much, you don't know how it helped me. Otherwise, I would have to create an internal storage system for each button between the tabs and remove it when editing the line.

                                          Yes, and a tool I am creating to help the 1 game community. How does it activate as resolved?
                                          Captura de tela de 2020-08-19 08-05-11.png

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

                                          @Gutks said in Pushbutton crashed.:

                                          How does it activate as resolved

                                          Either at bottom of page Topic Tools button, or if you feel a particular post answered it the vertical ... button at the right on that post.

                                          Pl45m4P 1 Reply Last reply
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