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comboBox runtime enable/disable

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  • 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
                                        1
                                        • M mpergand

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

                                          TheCipo76T Offline
                                          TheCipo76T Offline
                                          TheCipo76
                                          wrote on last edited by TheCipo76
                                          #28

                                          Finally works!

                                          i passed no parameters to the function ATTDIS():

                                          call the function then
                                          i check with a loop all members of array (with "for" i index) and when
                                          find "ESTERNA" enable comboFornitore[i]
                                          when find "INTERNA" disable comboFornitore[i]

                                          Thanks to all for patience and help gived

                                          1 Reply Last reply
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