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comboBox runtime enable/disable

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  • TheCipo76T TheCipo76

    i've created an array of 10 ComboBox populated from DB
    with this code:

    q.prepare("Select RAGSOC from FORNITORI order by RAGSOC");
        for (int i = 0; i < 10; i++) {
            array_Fornitore[i] = new QComboBox;
            ui->gridLayout_5->addWidget(array_Fornitore[i]);
            array_Fornitore[i]->setFixedWidth(300);
            array_Fornitore[i]->setFixedHeight(30);
            //Caricamento Combobox FORNITORE DA DATABASE
            if (q.exec()) {
                QSqlQueryModel *tModel = new QSqlQueryModel(this);
                tModel->setQuery(q);
                array_Fornitore[i]->setModel(tModel);
            }
            array_Fornitore[i]->setDisabled(true);
        }
    

    then i try to enable with this code (on pushbutton click):

    if (array_Origine[i]->currentText() == "INTERNA"){
                            array_Fornitore[i]->setEnabled(true);
                            //array_Fornitore[i]->clear();
                            return;
                    }
    
    TheCipo76T Offline
    TheCipo76T Offline
    TheCipo76
    wrote on last edited by
    #8

    @TheCipo76
    i have to do this without pushbutton..

    i read something about QEvent..

    is the right and only way?

    1 Reply Last reply
    0
    • TheCipo76T TheCipo76

      @SGaist
      i'm checking array_Origine[i]..
      depending to it i disable array_Fornitore[i]

      why you tell me that is the same combobox??

      SGaistS Offline
      SGaistS Offline
      SGaist
      Lifetime Qt Champion
      wrote on last edited by
      #9

      @TheCipo76 said in comboBox runtime enable/disable:

      @SGaist
      i'm checking array_Origine[i]..
      depending to it i disable array_Fornitore[i]

      why you tell me that is the same combobox??

      My bad, the code renderer mislead me.

      Anyway, how did you ensure that you are correctly going through that if ?

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

      TheCipo76T 1 Reply Last reply
      0
      • SGaistS SGaist

        @TheCipo76 said in comboBox runtime enable/disable:

        @SGaist
        i'm checking array_Origine[i]..
        depending to it i disable array_Fornitore[i]

        why you tell me that is the same combobox??

        My bad, the code renderer mislead me.

        Anyway, how did you ensure that you are correctly going through that if ?

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

        @SGaist said in comboBox runtime enable/disable:

        Anyway, how did you ensure that you are correctly going through that if ?

        on pushbutton click i check all (one by one) members of my form with a loop
        when arrive to this "if" i've already checked others widget ( arrays of combobox and lineedit)

        with a dedicated pushbutton i can enable / disable array_Fornitore[i] combobox
        but i wanto to do it without 10 button (array have 10 item) and 10 click!

        when i select (click)"INTERNA" in combobox array_Origine[i] i want disable array_Fornitore[i]
        without any other click and in real time.

        1 Reply Last reply
        0
        • SGaistS Offline
          SGaistS Offline
          SGaist
          Lifetime Qt Champion
          wrote on last edited by
          #11

          That's clear, what I'm asking is whether you used the debugger or a simple qDebug statement to ensure that your code went through the if that is supposed to disable the other combo box.

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

          TheCipo76T 1 Reply Last reply
          0
          • SGaistS SGaist

            That's clear, what I'm asking is whether you used the debugger or a simple qDebug statement to ensure that your code went through the if that is supposed to disable the other combo box.

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

            @SGaist
            i've check it with a simple QMessageBox inside the if statement:
            my code went throught the if.

            Cobra91151C 1 Reply Last reply
            0
            • TheCipo76T TheCipo76

              @SGaist
              i've check it with a simple QMessageBox inside the if statement:
              my code went throught the if.

              Cobra91151C Offline
              Cobra91151C Offline
              Cobra91151
              wrote on last edited by Cobra91151
              #13

              @TheCipo76

              Hi! You can also try to disable/enable the specific item of QComboBox like this:

              Disable:

              qobject_cast<QStandardItemModel*>(comboBox->model())->item(0)->setEnabled(false);
              

              Enable:

              qobject_cast<QStandardItemModel*>(comboBox->model())->item(0)->setEnabled(true);
              

              This code disables/enables the first combobox item.

              Also if you want to disable/enable the combobox, you can simplify it with connects. For example, when you select the value from the 1st combobox (signal activated) then emit your signal to disable the second combobox.

              T 1 Reply Last reply
              0
              • SGaistS Offline
                SGaistS Offline
                SGaist
                Lifetime Qt Champion
                wrote on last edited by
                #14

                Silly question: do you have any logic that re-enables that combo box ?

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

                TheCipo76T 1 Reply Last reply
                0
                • SGaistS SGaist

                  Silly question: do you have any logic that re-enables that combo box ?

                  TheCipo76T Offline
                  TheCipo76T Offline
                  TheCipo76
                  wrote on last edited by TheCipo76
                  #15

                  @SGaist
                  yes but work only with a pusbutton click

                  i think that i have to use the click event for enable / disable in real time

                  but combobox is added dinamically in runtime..

                  i've tried with:

                  connect(array_Fornitore[i], SIGNAL(clicked()), this, SLOT(ATTDIS(int i)));
                  

                  Dialog .cpp

                      void ATTDIS(int i) {
                      if (array_Origine[i].currentText == "ESTERNA") {
                          array_Fornitore[i]->setDisabled(false);
                      }
                      if (array_Origine[i].currentText == "INTERNA") {
                          array_Fornitore[i]->setDisabled(true);
                      }
                  }
                  }
                  

                  dialog .h

                  void ATTDIS(int i);
                  

                  but don't work..
                  (array_Origine[i] use of undeclared identifier)
                  (array_Fornitore[i] use of undeclared identifier)
                  how can i pass array_Orgine[i] and array_Fornitore[i] to the function??

                  JonBJ M 2 Replies Last reply
                  0
                  • TheCipo76T TheCipo76

                    @SGaist
                    yes but work only with a pusbutton click

                    i think that i have to use the click event for enable / disable in real time

                    but combobox is added dinamically in runtime..

                    i've tried with:

                    connect(array_Fornitore[i], SIGNAL(clicked()), this, SLOT(ATTDIS(int i)));
                    

                    Dialog .cpp

                        void ATTDIS(int i) {
                        if (array_Origine[i].currentText == "ESTERNA") {
                            array_Fornitore[i]->setDisabled(false);
                        }
                        if (array_Origine[i].currentText == "INTERNA") {
                            array_Fornitore[i]->setDisabled(true);
                        }
                    }
                    }
                    

                    dialog .h

                    void ATTDIS(int i);
                    

                    but don't work..
                    (array_Origine[i] use of undeclared identifier)
                    (array_Fornitore[i] use of undeclared identifier)
                    how can i pass array_Orgine[i] and array_Fornitore[i] to the function??

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

                    @TheCipo76
                    No offence intended, but from the same sort of thing in your previous posts you might like to read up on variable scope. And if you do understand that for normal variables, exactly the same applies when they are arrays.

                    Rather than worrying about how to pass these arrays as parameters each time to slots and other individual functions, wouldn't your code logic be simpler if they were defined as member variables of your class (the dialog)?

                    TheCipo76T 1 Reply Last reply
                    2
                    • JonBJ JonB

                      @TheCipo76
                      No offence intended, but from the same sort of thing in your previous posts you might like to read up on variable scope. And if you do understand that for normal variables, exactly the same applies when they are arrays.

                      Rather than worrying about how to pass these arrays as parameters each time to slots and other individual functions, wouldn't your code logic be simpler if they were defined as member variables of your class (the dialog)?

                      TheCipo76T Offline
                      TheCipo76T Offline
                      TheCipo76
                      wrote on last edited by TheCipo76
                      #17

                      @JonB
                      this is my dialog .h:

                      class inserisciarticolo : public QDialog
                      {
                          Q_OBJECT
                      
                      public:
                          explicit inserisciarticolo(QWidget *parent = nullptr);
                          ~inserisciarticolo();
                      
                      
                      private slots:
                      
                          void on_pushButton_Annulla_clicked();
                      
                          void on_pushButton_Inserisci_clicked();
                      
                          //void ATTDIS(int i);
                      
                      private:
                          Ui::inserisciarticolo *ui;
                      
                          QSqlDatabase aDatabase;
                          QSqlQuery *aModel;
                      
                          //Array Componenti
                          QLineEdit *array_Codice[10];
                          QLineEdit *array_Descrizione[10];
                          QSpinBox *array_Qta[10];
                          QComboBox *array_Origine[10];  //<--------------------
                          QComboBox *array_Fornitore[10]; //<------------------
                      
                      1 Reply Last reply
                      0
                      • TheCipo76T TheCipo76

                        @SGaist
                        yes but work only with a pusbutton click

                        i think that i have to use the click event for enable / disable in real time

                        but combobox is added dinamically in runtime..

                        i've tried with:

                        connect(array_Fornitore[i], SIGNAL(clicked()), this, SLOT(ATTDIS(int i)));
                        

                        Dialog .cpp

                            void ATTDIS(int i) {
                            if (array_Origine[i].currentText == "ESTERNA") {
                                array_Fornitore[i]->setDisabled(false);
                            }
                            if (array_Origine[i].currentText == "INTERNA") {
                                array_Fornitore[i]->setDisabled(true);
                            }
                        }
                        }
                        

                        dialog .h

                        void ATTDIS(int i);
                        

                        but don't work..
                        (array_Origine[i] use of undeclared identifier)
                        (array_Fornitore[i] use of undeclared identifier)
                        how can i pass array_Orgine[i] and array_Fornitore[i] to the function??

                        M Offline
                        M Offline
                        mpergand
                        wrote on last edited by
                        #18

                        @TheCipo76 said in comboBox runtime enable/disable:

                        connect(array_Fornitore[i], SIGNAL(clicked()), this, SLOT(ATTDIS(int i)));

                        You need to capture the var i in a lambda:

                        connect(array_Fornitore[i], &QComboBox::clicked, [i]() 
                        { 
                        ATTDIS(i);
                        });
                        
                        TheCipo76T 2 Replies Last reply
                        2
                        • M mpergand

                          @TheCipo76 said in comboBox runtime enable/disable:

                          connect(array_Fornitore[i], SIGNAL(clicked()), this, SLOT(ATTDIS(int i)));

                          You need to capture the var i in a lambda:

                          connect(array_Fornitore[i], &QComboBox::clicked, [i]() 
                          { 
                          ATTDIS(i);
                          });
                          
                          TheCipo76T Offline
                          TheCipo76T Offline
                          TheCipo76
                          wrote on last edited by
                          #19

                          @mpergand
                          it's very interesting..

                          i can capture i var and pass it to a slot function
                          if i have understand..

                          but once i have done it what i have to do??
                          slot function do what i need?

                          1 Reply Last reply
                          0
                          • M Offline
                            M Offline
                            mpergand
                            wrote on last edited by
                            #20

                            The lambda function becomes the slot function.
                            You probably need to capture 'this' as well to get access to methods and vars of the class instance.

                            TheCipo76T 1 Reply Last reply
                            2
                            • M mpergand

                              The lambda function becomes the slot function.
                              You probably need to capture 'this' as well to get access to methods and vars of the class instance.

                              TheCipo76T Offline
                              TheCipo76T Offline
                              TheCipo76
                              wrote on last edited by TheCipo76
                              #21

                              @mpergand
                              thank you very much for your reply
                              but i don't think i'm able to do this..

                              now i try to learn about lamba expression

                              1 Reply Last reply
                              1
                              • TheCipo76T Offline
                                TheCipo76T Offline
                                TheCipo76
                                wrote on last edited by TheCipo76
                                #22
                                This post is deleted!
                                1 Reply Last reply
                                0
                                • M mpergand

                                  @TheCipo76 said in comboBox runtime enable/disable:

                                  connect(array_Fornitore[i], SIGNAL(clicked()), this, SLOT(ATTDIS(int i)));

                                  You need to capture the var i in a lambda:

                                  connect(array_Fornitore[i], &QComboBox::clicked, [i]() 
                                  { 
                                  ATTDIS(i);
                                  });
                                  
                                  TheCipo76T Offline
                                  TheCipo76T Offline
                                  TheCipo76
                                  wrote on last edited by TheCipo76
                                  #23

                                  @mpergand

                                  i've tried with this code:

                                  connect(array_Origine[i], SIGNAL(currentTextChanged(QString)) [i] () { ATTDIS(i);} );
                                  

                                  and with this:

                                  connect(array_Origine[i], SIGNAL(currentTextChanged(QString)) [this, i] () { ATTDIS(i);} );
                                  

                                  but give me this error:

                                  called object type 'char' is not a function or function pointer

                                  how can i solve it??

                                  void inserisciarticolo::ATTDIS(int i)
                                  {
                                      if (array_Origine[i]->currentText() == "ESTERNA") {
                                          array_Fornitore[i]->setDisabled(false);
                                          array_Fornitore[i]->repaint();
                                      }
                                      if (array_Origine[i]->currentText() == "INTERNA") {
                                          array_Fornitore[i]->setDisabled(true);
                                          array_Fornitore[i]->repaint();
                                      }
                                  
                                  }
                                  
                                  M 1 Reply Last reply
                                  0
                                  • TheCipo76T TheCipo76

                                    @mpergand

                                    i've tried with this code:

                                    connect(array_Origine[i], SIGNAL(currentTextChanged(QString)) [i] () { ATTDIS(i);} );
                                    

                                    and with this:

                                    connect(array_Origine[i], SIGNAL(currentTextChanged(QString)) [this, i] () { ATTDIS(i);} );
                                    

                                    but give me this error:

                                    called object type 'char' is not a function or function pointer

                                    how can i solve it??

                                    void inserisciarticolo::ATTDIS(int i)
                                    {
                                        if (array_Origine[i]->currentText() == "ESTERNA") {
                                            array_Fornitore[i]->setDisabled(false);
                                            array_Fornitore[i]->repaint();
                                        }
                                        if (array_Origine[i]->currentText() == "INTERNA") {
                                            array_Fornitore[i]->setDisabled(true);
                                            array_Fornitore[i]->repaint();
                                        }
                                    
                                    }
                                    
                                    M Offline
                                    M Offline
                                    mpergand
                                    wrote on last edited by
                                    #24

                                    @TheCipo76 said in comboBox runtime enable/disable:

                                    connect(array_Origine[i], SIGNAL(currentTextChanged(QString)) [this, i] () { ATTDIS(i);} );

                                    connect(array_Origine[i], &QComboBox::currentTextChanged) [this, i] (QString str) { ATTDIS(i);} );

                                    TheCipo76T 1 Reply Last reply
                                    0
                                    • M mpergand

                                      @TheCipo76 said in comboBox runtime enable/disable:

                                      connect(array_Origine[i], SIGNAL(currentTextChanged(QString)) [this, i] () { ATTDIS(i);} );

                                      connect(array_Origine[i], &QComboBox::currentTextChanged) [this, i] (QString str) { ATTDIS(i);} );

                                      TheCipo76T Offline
                                      TheCipo76T Offline
                                      TheCipo76
                                      wrote on last edited by TheCipo76
                                      #25

                                      @mpergand said in comboBox runtime enable/disable:

                                      connect(array_Origine[i], &QComboBox::currentTextChanged) [this, i] (QString str) { ATTDIS(i);} );

                                      don't work..

                                      'QString' does not refer to a value

                                      error: no matching member function for call to 'connect'

                                      1 Reply Last reply
                                      0
                                      • M Offline
                                        M Offline
                                        mpergand
                                        wrote on last edited by
                                        #26
                                        QComboBox box;
                                        box.setEditable(true);
                                        QObject::connect(&box,&QComboBox::currentTextChanged,[](QString str)
                                        {
                                        qDebug()<<str;
                                        });
                                        
                                        box.show();
                                        

                                        works as expected ....

                                        1 Reply Last reply
                                        1
                                        • M Offline
                                          M Offline
                                          mpergand
                                          wrote on last edited by mpergand
                                          #27

                                          sorry typo:
                                          connect(array_Origine[i], &QComboBox::currentTextChanged ) <- remove )
                                          [this, i] (QString str) { ATTDIS(i);} );

                                          TheCipo76T 1 Reply Last reply
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