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QDataStream serialze & deserialize 'myclass' pointer

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  • Taz742T Taz742

    @kshegunov
    Well, let's consider this case.
    What I wrote this is the server side.

    When I get it to the client side, if I get the same kind of list and get the value from it.
    for example:

        QList<faf> list;
    
        list.push_back(faf(2, 13));
        list.push_back(faf(15, 23));
        list.push_back(faf(30, 46));
    
        faf test = list[0];
        test.x = test.x * 2;
        test.y = test.y * 2;
    
        for (int i = 0; i < list.size(); i++) {
            qDebug() << list[i].x << list[i].y; //Prints the same values
        }
    
    
    

    If I want the object to change in the list.
    Is it right?

        QList<faf> list;
    
        list.push_back(faf(2, 13));
        list.push_back(faf(15, 23));
        list.push_back(faf(30, 46));
    
        faf *test = &list[0];
        test->x = test->x * 2;
        test->y = test->y * 2;
    
        for (int i = 0; i < list.size(); i++) {
            qDebug() << list[i].x << list[i].y; //list[0].x = 4 and list[0].y = 46;
        }
    
    kshegunovK Offline
    kshegunovK Offline
    kshegunov
    Moderators
    wrote on last edited by
    #12

    @Taz742 said in QDataStream serialze & deserialize 'myclass' pointer:

    // Prints the same values
    

    Of course it does, you're copying the object that's stored in the list and modifying the copy.

    If I want the object to change in the list.

    Why convert to pointers? Just use references:

    faf & test = list[0];
    test.x *= 2;
    test.y *= 2;
    

    Read and abide by the Qt Code of Conduct

    Taz742T 1 Reply Last reply
    2
    • kshegunovK kshegunov

      @Taz742 said in QDataStream serialze & deserialize 'myclass' pointer:

      // Prints the same values
      

      Of course it does, you're copying the object that's stored in the list and modifying the copy.

      If I want the object to change in the list.

      Why convert to pointers? Just use references:

      faf & test = list[0];
      test.x *= 2;
      test.y *= 2;
      
      Taz742T Offline
      Taz742T Offline
      Taz742
      wrote on last edited by Taz742
      #13

      @kshegunov good :))

      Now there are new problems.
      Recently everything was good.
      I do not know what happened to me or why.

      alt text

      C:\Users\User\Desktop\tazsmsorigin\enumeration.h:69: error: no match for 'operator>>' (operand types are 'QDataStream' and 'qint32 {aka int}')
           stream >> tempint; _class.UID = tempint;
                  ^
      C:\Users\User\Desktop\tazsmsorigin\enumeration.h:50: error: ambiguous overload for 'operator<<' (operand types are 'QDataStream' and 'int')
           stream  << static_cast<qint32>(_class.UID)
                   ^
      C:\Users\User\Desktop\tazsmsorigin\enumeration.h:46: error: no match for 'operator>>' (operand types are 'QDataStream' and 'bool')
           return stream >> _class.TChecked >> _class.Message;
                         ^
      

      Do what you want.

      kshegunovK 1 Reply Last reply
      0
      • Taz742T Taz742

        @kshegunov good :))

        Now there are new problems.
        Recently everything was good.
        I do not know what happened to me or why.

        alt text

        C:\Users\User\Desktop\tazsmsorigin\enumeration.h:69: error: no match for 'operator>>' (operand types are 'QDataStream' and 'qint32 {aka int}')
             stream >> tempint; _class.UID = tempint;
                    ^
        C:\Users\User\Desktop\tazsmsorigin\enumeration.h:50: error: ambiguous overload for 'operator<<' (operand types are 'QDataStream' and 'int')
             stream  << static_cast<qint32>(_class.UID)
                     ^
        C:\Users\User\Desktop\tazsmsorigin\enumeration.h:46: error: no match for 'operator>>' (operand types are 'QDataStream' and 'bool')
             return stream >> _class.TChecked >> _class.Message;
                           ^
        
        kshegunovK Offline
        kshegunovK Offline
        kshegunov
        Moderators
        wrote on last edited by
        #14

        Did you forget to include the <QDataStream> header?

        Read and abide by the Qt Code of Conduct

        Taz742T 1 Reply Last reply
        1
        • kshegunovK kshegunov

          Did you forget to include the <QDataStream> header?

          Taz742T Offline
          Taz742T Offline
          Taz742
          wrote on last edited by
          #15

          @kshegunov no. I have

          Do what you want.

          kshegunovK 1 Reply Last reply
          0
          • Taz742T Taz742

            @kshegunov no. I have

            kshegunovK Offline
            kshegunovK Offline
            kshegunov
            Moderators
            wrote on last edited by
            #16

            Then you need to follow the compiler errors, it has given you exact directions where the errors are:
            C:\Users\User\Desktop\tazsmsorigin\enumeration.h @ line 69

            error: no match for 'operator>>' (operand types are 'QDataStream' and 'qint32 {aka int}')

            I'm pretty sure this comes from not including the header. Also there's something amiss, it should be QDataStream & not QDataStream. Please post what's on line 69 in enumeration.h.

            Read and abide by the Qt Code of Conduct

            Taz742T 1 Reply Last reply
            2
            • kshegunovK kshegunov

              Then you need to follow the compiler errors, it has given you exact directions where the errors are:
              C:\Users\User\Desktop\tazsmsorigin\enumeration.h @ line 69

              error: no match for 'operator>>' (operand types are 'QDataStream' and 'qint32 {aka int}')

              I'm pretty sure this comes from not including the header. Also there's something amiss, it should be QDataStream & not QDataStream. Please post what's on line 69 in enumeration.h.

              Taz742T Offline
              Taz742T Offline
              Taz742
              wrote on last edited by Taz742
              #17

              @kshegunov
              Yes the library was nat included, but I had it in globaldefines.h file.
              He has caused a redifination proxy, QDataStream also has been described in MySocket.h file.

              Do what you want.

              kshegunovK 1 Reply Last reply
              0
              • Taz742T Taz742

                @kshegunov
                Yes the library was nat included, but I had it in globaldefines.h file.
                He has caused a redifination proxy, QDataStream also has been described in MySocket.h file.

                kshegunovK Offline
                kshegunovK Offline
                kshegunov
                Moderators
                wrote on last edited by
                #18

                @Taz742 said in QDataStream serialze & deserialize 'myclass' pointer:

                He has caused a redifination proxy, QDataStream also has been described in MySocket.h file.

                I don't follow.

                Read and abide by the Qt Code of Conduct

                Taz742T 2 Replies Last reply
                0
                • kshegunovK kshegunov

                  @Taz742 said in QDataStream serialze & deserialize 'myclass' pointer:

                  He has caused a redifination proxy, QDataStream also has been described in MySocket.h file.

                  I don't follow.

                  Taz742T Offline
                  Taz742T Offline
                  Taz742
                  wrote on last edited by
                  #19

                  @kshegunov I had code again mysocket.h, I taught at different places how to deal with my classes.

                  Do what you want.

                  1 Reply Last reply
                  0
                  • kshegunovK kshegunov

                    @Taz742 said in QDataStream serialze & deserialize 'myclass' pointer:

                    He has caused a redifination proxy, QDataStream also has been described in MySocket.h file.

                    I don't follow.

                    Taz742T Offline
                    Taz742T Offline
                    Taz742
                    wrote on last edited by Taz742
                    #20

                    @kshegunov @VRonin
                    How to handle QDataStream to my classes, this are stored in one 'header' file.
                    It's uncomfortable for me because I have many issues.
                    I learnt to my classes QDataStream >> and << operators.

                    For Example:

                    #ifndef POINT3D_H
                    #define POINT3D_H
                    
                    #include "QObject"
                    #include "QDataStream"
                    
                    class Point3D
                    {
                    public:
                        Point3D();
                        int x;
                        int y;
                        int z;
                    
                        Point3D(int _x, int _y, int _z) {
                            this->x = _x;
                            this->y = _y;
                            this->z = _z;
                        }
                    
                        friend QDataStream & operator << (QDataStream &stream, const Point3D &obj);
                        friend QDataStream & operator >> (QDataStream &stream, Point3D &obj);
                    };
                    
                    Q_DECLARE_TYPEINFO(Point3D, Q_MOVABLE_TYPE);
                    
                    #endif // POINT3D_H
                    
                    #include "point3d.h"
                    
                    Point3D::Point3D()
                    {
                    
                    }
                    
                    QDataStream & operator << (QDataStream &stream, const Point3D &obj) {
                        stream << static_cast<qint32>(obj.x) << static_cast<qint32>(obj.y) << static_cast<qint32>(obj.z);
                        return stream;
                    }
                    
                    QDataStream & operator >> (QDataStream &stream, Point3D &obj) {
                        qint32 tempint;
                        stream >> tempint; obj.x = static_cast<int>(tempint);
                        stream >> tempint; obj.y = static_cast<int>(tempint);
                        stream >> tempint; obj.z = static_cast<int>(tempint);
                    
                        return stream;
                    }
                    

                    I want to be sure that this will work from anywhere. Can you confirm it?

                    Do what you want.

                    kshegunovK 1 Reply Last reply
                    0
                    • Taz742T Taz742

                      @kshegunov @VRonin
                      How to handle QDataStream to my classes, this are stored in one 'header' file.
                      It's uncomfortable for me because I have many issues.
                      I learnt to my classes QDataStream >> and << operators.

                      For Example:

                      #ifndef POINT3D_H
                      #define POINT3D_H
                      
                      #include "QObject"
                      #include "QDataStream"
                      
                      class Point3D
                      {
                      public:
                          Point3D();
                          int x;
                          int y;
                          int z;
                      
                          Point3D(int _x, int _y, int _z) {
                              this->x = _x;
                              this->y = _y;
                              this->z = _z;
                          }
                      
                          friend QDataStream & operator << (QDataStream &stream, const Point3D &obj);
                          friend QDataStream & operator >> (QDataStream &stream, Point3D &obj);
                      };
                      
                      Q_DECLARE_TYPEINFO(Point3D, Q_MOVABLE_TYPE);
                      
                      #endif // POINT3D_H
                      
                      #include "point3d.h"
                      
                      Point3D::Point3D()
                      {
                      
                      }
                      
                      QDataStream & operator << (QDataStream &stream, const Point3D &obj) {
                          stream << static_cast<qint32>(obj.x) << static_cast<qint32>(obj.y) << static_cast<qint32>(obj.z);
                          return stream;
                      }
                      
                      QDataStream & operator >> (QDataStream &stream, Point3D &obj) {
                          qint32 tempint;
                          stream >> tempint; obj.x = static_cast<int>(tempint);
                          stream >> tempint; obj.y = static_cast<int>(tempint);
                          stream >> tempint; obj.z = static_cast<int>(tempint);
                      
                          return stream;
                      }
                      

                      I want to be sure that this will work from anywhere. Can you confirm it?

                      kshegunovK Offline
                      kshegunovK Offline
                      kshegunov
                      Moderators
                      wrote on last edited by
                      #21

                      @Taz742 said in QDataStream serialze & deserialize 'myclass' pointer:

                      I want to be sure that this will work from anywhere. Can you confirm it?

                      I don't understand the question, could you elaborate.

                      Read and abide by the Qt Code of Conduct

                      Taz742T 1 Reply Last reply
                      0
                      • kshegunovK kshegunov

                        @Taz742 said in QDataStream serialze & deserialize 'myclass' pointer:

                        I want to be sure that this will work from anywhere. Can you confirm it?

                        I don't understand the question, could you elaborate.

                        Taz742T Offline
                        Taz742T Offline
                        Taz742
                        wrote on last edited by
                        #22

                        @kshegunov said in QDataStream serialze & deserialize 'myclass' pointer:

                        I don't understand the question, could you elaborate.

                        I have class Point3D which know how to behave when datastream requires input(<<) or output(>>) operators.
                        I want to know if it will works from anyclasses, for example: from mainwindows and etc..

                        Do what you want.

                        kshegunovK 1 Reply Last reply
                        0
                        • Taz742T Taz742

                          @kshegunov said in QDataStream serialze & deserialize 'myclass' pointer:

                          I don't understand the question, could you elaborate.

                          I have class Point3D which know how to behave when datastream requires input(<<) or output(>>) operators.
                          I want to know if it will works from anyclasses, for example: from mainwindows and etc..

                          kshegunovK Offline
                          kshegunovK Offline
                          kshegunov
                          Moderators
                          wrote on last edited by
                          #23

                          Why wouldn't it? As long as the functions have declarations at the point of usage it's the linker's problem to tie it all together ... it's the singular purpose for which the linker exists actually.

                          Read and abide by the Qt Code of Conduct

                          Taz742T 1 Reply Last reply
                          3
                          • kshegunovK kshegunov

                            Why wouldn't it? As long as the functions have declarations at the point of usage it's the linker's problem to tie it all together ... it's the singular purpose for which the linker exists actually.

                            Taz742T Offline
                            Taz742T Offline
                            Taz742
                            wrote on last edited by
                            #24

                            @kshegunov Now I'm sure. thanks.

                            Do what you want.

                            1 Reply Last reply
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