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comboBox runtime enable/disable

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  • 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
                        0
                        • Cobra91151C Cobra91151

                          @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 Offline
                          T Offline
                          TruongNguyen
                          wrote on last edited by
                          #29

                          @Cobra91151 Thank you. It worked.

                          1 Reply Last reply
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