Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. General and Desktop
  4. How Can i get array in another class
Forum Updated to NodeBB v4.3 + New Features

How Can i get array in another class

Scheduled Pinned Locked Moved Unsolved General and Desktop
46 Posts 8 Posters 8.0k Views 3 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • 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 Online
          JonBJ Online
          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
                                        0
                                        • D dziko147

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

                                          jsulmJ Offline
                                          jsulmJ Offline
                                          jsulm
                                          Lifetime Qt Champion
                                          wrote on last edited by
                                          #36

                                          @dziko147 Yes, I can: use one instance of the class instead of two...

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

                                          1 Reply Last reply
                                          2

                                          • Login

                                          • Login or register to search.
                                          • First post
                                            Last post
                                          0
                                          • Categories
                                          • Recent
                                          • Tags
                                          • Popular
                                          • Users
                                          • Groups
                                          • Search
                                          • Get Qt Extensions
                                          • Unsolved