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How Can i get array in another class

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  • D dziko147

    @CP71 thanks for your reply .
    I used your solution but still get array empty.

    I set data in Inputs in a Slot called after clicking in button .
    It cause problem ?

    void UploadCSV::on_parambtn_2_clicked()
    {
    
        int compteur=0;
        QString cell0;
        QString cell3 ;
        for(int i=0;i<ui->tablewidget->rowCount();i++){
    
            QTableWidgetItem *cell7 = ui->tablewidget->item(i,7);
    
            QVariant myData7 = cell7->data(Qt::DisplayRole);
            if (myData7=="Core_meas"){
                cell0  = ui->tablewidget->item(i,0)->text();
                cell3 = ui->tablewidget->item(i,3)->text();
                Inputs[compteur]=cell3;
                qDebug() << "Inputs baby"<<Inputs[compteur] ;
                compteur++;
            }
    
        }
    
    
    }
    
    SGaistS Offline
    SGaistS Offline
    SGaist
    Lifetime Qt Champion
    wrote on last edited by
    #16

    @dziko147 you should go back to the basics first: séparation of responsibilities.

    There's no reason for you child class to have an instance of your GUI class in it.

    From the looks of it, your GUI is responsible to generate that array and it looks as well as the class processing that array should receive it from the GUI object. Hence there's no need for it to know anything or contain an object of your GUI class.

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

    1 Reply Last reply
    3
    • D Offline
      D Offline
      dziko147
      wrote on last edited by
      #17

      @SGaist exact. I set data in my array from GUI element .
      if i understand you. I don't need to create an instance of my class .
      So how can i call the array from the other class

      1 Reply Last reply
      0
      • A Offline
        A Offline
        anh_ph
        wrote on last edited by
        #18

        If class B is child of class A, then you can do sth like this in class B

        classA *clsA= dynamic_cast <classA*> (parent());
        clsA->funcToGetData();
        
        1 Reply Last reply
        0
        • D Offline
          D Offline
          dziko147
          wrote on last edited by
          #19

          @anh_ph the funcToGetData(); can be a slot wich get data from GUI elements ?

          And if classA isn't child od classB . How can i call it

          JonBJ A 2 Replies Last reply
          0
          • D dziko147

            @anh_ph the funcToGetData(); can be a slot wich get data from GUI elements ?

            And if classA isn't child od classB . How can i call it

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

            @dziko147 said in How Can i get array in another class:

            And if classA isn't child od classB . How can i call it

            The code you were shown attempts to cast the parent() to classA. If your classA instance is not related to you classB instance through its parent, then use whatever you have for the desired classA instance....

            I'm not sure but you seem not to understand the difference between a class and an instance (or object)? If that is the case I suggest you read up to understand, as this is vital in OO programming.

            1 Reply Last reply
            1
            • D Offline
              D Offline
              dziko147
              wrote on last edited by
              #21

              @JonB no i know the difference between instance and class .
              But honestly i have no idea what parent() mean .
              And if we say a classA is a child of classB we mean classA is inherited drom classB .

              Thank you

              jsulmJ 1 Reply Last reply
              0
              • D dziko147

                @JonB no i know the difference between instance and class .
                But honestly i have no idea what parent() mean .
                And if we say a classA is a child of classB we mean classA is inherited drom classB .

                Thank you

                jsulmJ Offline
                jsulmJ Offline
                jsulm
                Lifetime Qt Champion
                wrote on last edited by
                #22

                @dziko147 said in How Can i get array in another class:

                we mean classA is inherited drom classB

                No, we don't.
                See https://doc.qt.io/qt-5/objecttrees.html
                Parent/child is not about inheritance it is about relationships between QObject based classes.

                https://forum.qt.io/topic/113070/qt-code-of-conduct

                1 Reply Last reply
                0
                • D dziko147

                  @anh_ph the funcToGetData(); can be a slot wich get data from GUI elements ?

                  And if classA isn't child od classB . How can i call it

                  A Offline
                  A Offline
                  anh_ph
                  wrote on last edited by
                  #23

                  @dziko147 said in How Can i get array in another class:

                  @anh_ph the funcToGetData(); can be a slot wich get data from GUI elements ?

                  And if classA isn't child od classB . How can i call it

                  If you want to get data from classA, you must get an exact object of it, which works with the data. If you can't do it, then try to apply singleton to classA.
                  Btw, you can't get an array in another class, but you can get an array in an object of another class.

                  1 Reply Last reply
                  0
                  • D Offline
                    D Offline
                    dziko147
                    wrote on last edited by
                    #24

                    to resume what should i do to set data from GUI element in an array then get this array in another class .

                    Btw I tried many solution but usually I get an empty array in the other class :)

                    jsulmJ 1 Reply Last reply
                    0
                    • D dziko147

                      to resume what should i do to set data from GUI element in an array then get this array in another class .

                      Btw I tried many solution but usually I get an empty array in the other class :)

                      jsulmJ Offline
                      jsulmJ Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by
                      #25

                      @dziko147 said in How Can i get array in another class:

                      but usually I get an empty array in the other class

                      I guess that's because you have more than one instance of the class from which you get your array.
                      Please post your code. Passing data from one object to another is actually a trivial exercise.

                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                      1 Reply Last reply
                      1
                      • D Offline
                        D Offline
                        dziko147
                        wrote on last edited by dziko147
                        #26

                        @jsulm

                        // classeA.h
                        std::array<QString,25> Inputs;
                        
                        // ClassA.cpp "UploadCSV"
                        void UploadCSV::on_parambtn_2_clicked()
                        {
                        
                            int compteur=0;
                            QString cell0;
                            QString cell3 ;
                            for(int i=0;i<ui->tablewidget->rowCount();i++){
                        
                                QTableWidgetItem *cell7 = ui->tablewidget->item(i,7);
                        
                                QVariant myData7 = cell7->data(Qt::DisplayRole);
                                if (myData7=="Core_meas"){
                                    cell0  = ui->tablewidget->item(i,0)->text();
                                    cell3 = ui->tablewidget->item(i,3)->text();
                                    Inputs[compteur]=cell3;
                                    qDebug() << "Inputs baby"<<Inputs[compteur] ;
                                    compteur++;
                                }
                        
                            }
                        
                        
                        }
                        

                        //in classB.

                        UploadCSV *up;

                        //in classB.cpp

                        up=new UploadCSV();
                        for(size_t i=0;i<up.Inputs->size();i++){
                        qqDebug() << "this is data",up.Inputs[i]
                        
                        
                        jsulmJ Pl45m4P CP71C 3 Replies Last reply
                        0
                        • D dziko147

                          @jsulm

                          // classeA.h
                          std::array<QString,25> Inputs;
                          
                          // ClassA.cpp "UploadCSV"
                          void UploadCSV::on_parambtn_2_clicked()
                          {
                          
                              int compteur=0;
                              QString cell0;
                              QString cell3 ;
                              for(int i=0;i<ui->tablewidget->rowCount();i++){
                          
                                  QTableWidgetItem *cell7 = ui->tablewidget->item(i,7);
                          
                                  QVariant myData7 = cell7->data(Qt::DisplayRole);
                                  if (myData7=="Core_meas"){
                                      cell0  = ui->tablewidget->item(i,0)->text();
                                      cell3 = ui->tablewidget->item(i,3)->text();
                                      Inputs[compteur]=cell3;
                                      qDebug() << "Inputs baby"<<Inputs[compteur] ;
                                      compteur++;
                                  }
                          
                              }
                          
                          
                          }
                          

                          //in classB.

                          UploadCSV *up;

                          //in classB.cpp

                          up=new UploadCSV();
                          for(size_t i=0;i<up.Inputs->size();i++){
                          qqDebug() << "this is data",up.Inputs[i]
                          
                          
                          jsulmJ Offline
                          jsulmJ Offline
                          jsulm
                          Lifetime Qt Champion
                          wrote on last edited by
                          #27

                          @dziko147 Sorry, I fail to understand the code you posted.
                          What type is myclasseA? And why do you access Inputs from two different objects (up and myclasseA)?
                          It really looks like you have two different instances of UploadCSV...

                          https://forum.qt.io/topic/113070/qt-code-of-conduct

                          1 Reply Last reply
                          0
                          • D dziko147

                            @jsulm

                            // classeA.h
                            std::array<QString,25> Inputs;
                            
                            // ClassA.cpp "UploadCSV"
                            void UploadCSV::on_parambtn_2_clicked()
                            {
                            
                                int compteur=0;
                                QString cell0;
                                QString cell3 ;
                                for(int i=0;i<ui->tablewidget->rowCount();i++){
                            
                                    QTableWidgetItem *cell7 = ui->tablewidget->item(i,7);
                            
                                    QVariant myData7 = cell7->data(Qt::DisplayRole);
                                    if (myData7=="Core_meas"){
                                        cell0  = ui->tablewidget->item(i,0)->text();
                                        cell3 = ui->tablewidget->item(i,3)->text();
                                        Inputs[compteur]=cell3;
                                        qDebug() << "Inputs baby"<<Inputs[compteur] ;
                                        compteur++;
                                    }
                            
                                }
                            
                            
                            }
                            

                            //in classB.

                            UploadCSV *up;

                            //in classB.cpp

                            up=new UploadCSV();
                            for(size_t i=0;i<up.Inputs->size();i++){
                            qqDebug() << "this is data",up.Inputs[i]
                            
                            
                            Pl45m4P Offline
                            Pl45m4P Offline
                            Pl45m4
                            wrote on last edited by Pl45m4
                            #28

                            @dziko147 said in How Can i get array in another class:

                            ,myclasseA.Inputs[i]

                            Why do you have myClasseA there, when the object is up
                            Try up.Inputs[i]

                            (Corrected, thx @jsulm )


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

                            ~E. W. Dijkstra

                            jsulmJ 1 Reply Last reply
                            0
                            • Pl45m4P Pl45m4

                              @dziko147 said in How Can i get array in another class:

                              ,myclasseA.Inputs[i]

                              Why do you have myClasseA there, when the object is up
                              Try up.Inputs[i]

                              (Corrected, thx @jsulm )

                              jsulmJ Offline
                              jsulmJ Offline
                              jsulm
                              Lifetime Qt Champion
                              wrote on last edited by
                              #29

                              @Pl45m4 said in How Can i get array in another class:

                              when the object is UploadCSV

                              UploadCSV seems to be the class, not object

                              https://forum.qt.io/topic/113070/qt-code-of-conduct

                              1 Reply Last reply
                              0
                              • D Offline
                                D Offline
                                dziko147
                                wrote on last edited by
                                #30

                                @jsulm sorry I edited the code .

                                I gave the expamle of classA and ClassB to be clearer .

                                ClassA (UploadCSV ) is a Qwidget : Qdialog

                                ClassB (Backend) is QObject .

                                jsulmJ 1 Reply Last reply
                                0
                                • D dziko147

                                  @jsulm

                                  // classeA.h
                                  std::array<QString,25> Inputs;
                                  
                                  // ClassA.cpp "UploadCSV"
                                  void UploadCSV::on_parambtn_2_clicked()
                                  {
                                  
                                      int compteur=0;
                                      QString cell0;
                                      QString cell3 ;
                                      for(int i=0;i<ui->tablewidget->rowCount();i++){
                                  
                                          QTableWidgetItem *cell7 = ui->tablewidget->item(i,7);
                                  
                                          QVariant myData7 = cell7->data(Qt::DisplayRole);
                                          if (myData7=="Core_meas"){
                                              cell0  = ui->tablewidget->item(i,0)->text();
                                              cell3 = ui->tablewidget->item(i,3)->text();
                                              Inputs[compteur]=cell3;
                                              qDebug() << "Inputs baby"<<Inputs[compteur] ;
                                              compteur++;
                                          }
                                  
                                      }
                                  
                                  
                                  }
                                  

                                  //in classB.

                                  UploadCSV *up;

                                  //in classB.cpp

                                  up=new UploadCSV();
                                  for(size_t i=0;i<up.Inputs->size();i++){
                                  qqDebug() << "this is data",up.Inputs[i]
                                  
                                  
                                  CP71C Offline
                                  CP71C Offline
                                  CP71
                                  wrote on last edited by
                                  #31

                                  @dziko147 said in How Can i get array in another class:

                                  up=new UploadCSV();
                                  for(size_t i=0;i<up.Inputs->size();i++){
                                  qqDebug() << "this is data",up.Inputs[i]

                                  Sorry, who calls the on_parambtn_2_clicked() function?

                                  1 Reply Last reply
                                  1
                                  • D dziko147

                                    @jsulm sorry I edited the code .

                                    I gave the expamle of classA and ClassB to be clearer .

                                    ClassA (UploadCSV ) is a Qwidget : Qdialog

                                    ClassB (Backend) is QObject .

                                    jsulmJ Offline
                                    jsulmJ Offline
                                    jsulm
                                    Lifetime Qt Champion
                                    wrote on last edited by
                                    #32

                                    @dziko147 Is this your real code:

                                    up=new UploadCSV();
                                    for(size_t i=0;i<up.Inputs->size();i++){
                                    qqDebug() << "this is data",up.Inputs[i]
                                    

                                    ?
                                    Because Items is filled when UploadCSV::on_parambtn_2_clicked() is called (at least according to code you posted). But you're printing Inputs just after creating UploadCSV instance (up)! So why should there be anything in Inputs?

                                    https://forum.qt.io/topic/113070/qt-code-of-conduct

                                    D 1 Reply Last reply
                                    3
                                    • D Offline
                                      D Offline
                                      dziko147
                                      wrote on last edited by
                                      #33

                                      @CP71 it's called in UploadCSV class (classA) .

                                      and inside this function I set data in Inputs[] .

                                      jsulmJ 1 Reply Last reply
                                      0
                                      • D dziko147

                                        @CP71 it's called in UploadCSV class (classA) .

                                        and inside this function I set data in Inputs[] .

                                        jsulmJ Offline
                                        jsulmJ Offline
                                        jsulm
                                        Lifetime Qt Champion
                                        wrote on last edited by jsulm
                                        #34

                                        @dziko147 said in How Can i get array in another class:

                                        it's called in UploadCSV class (classA) .

                                        Where exactly?! And what is classA?! This all is really confusing!
                                        up != classA

                                        https://forum.qt.io/topic/113070/qt-code-of-conduct

                                        D 1 Reply Last reply
                                        1
                                        • jsulmJ jsulm

                                          @dziko147 Is this your real code:

                                          up=new UploadCSV();
                                          for(size_t i=0;i<up.Inputs->size();i++){
                                          qqDebug() << "this is data",up.Inputs[i]
                                          

                                          ?
                                          Because Items is filled when UploadCSV::on_parambtn_2_clicked() is called (at least according to code you posted). But you're printing Inputs just after creating UploadCSV instance (up)! So why should there be anything in Inputs?

                                          D Offline
                                          D Offline
                                          dziko147
                                          wrote on last edited by
                                          #35

                                          @jsulm yes i understand you . So can you suggest a way to do this correctly ?

                                          jsulmJ SGaistS 2 Replies Last reply
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