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  • P Offline
    P Offline
    Payx
    wrote on last edited by
    #32

    Thanks for your help,

    I got one error

    undefined reference to 'MainWindow::dominantColor()'

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    0
    • VRoninV Offline
      VRoninV Offline
      VRonin
      wrote on last edited by VRonin
      #33

      colour vs color

      "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
      ~Napoleon Bonaparte

      On a crusade to banish setIndexWidget() from the holy land of Qt

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      1
      • P Offline
        P Offline
        Payx
        wrote on last edited by
        #34

        thats wasnt a simple letter that occured an error,

        undefined reference to 'MainWindow::dominantColour()'
        undefined reference to ''MainWindow::fillSection()'

        1 Reply Last reply
        0
        • SGaistS Offline
          SGaistS Offline
          SGaist
          Lifetime Qt Champion
          wrote on last edited by
          #35

          Because they are not part of MainWindow. Take a look again a the function signature.

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

          P 1 Reply Last reply
          1
          • SGaistS SGaist

            Because they are not part of MainWindow. Take a look again a the function signature.

            P Offline
            P Offline
            Payx
            wrote on last edited by
            #36

            @SGaist

            Here my window.h

            private slots:
            	void on_push_clicked();
            	QColor	dominantColour();
            	void fillSection();
            
            	void on_push2_clicked();
            

            You said my function is not part of MainWindow, so i try to add MainWindow::

            void MainWindow::fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour) {
            

            and its said prototype for void Main...... does not match any in class 'MainWindow'

            kshegunovK 1 Reply Last reply
            0
            • SGaistS Offline
              SGaistS Offline
              SGaist
              Lifetime Qt Champion
              wrote on last edited by
              #37

              Method signature mismatch.

              Note: neither dominantColour nor fillSection make sense in the slots category.

              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
              2
              • P Payx

                @SGaist

                Here my window.h

                private slots:
                	void on_push_clicked();
                	QColor	dominantColour();
                	void fillSection();
                
                	void on_push2_clicked();
                

                You said my function is not part of MainWindow, so i try to add MainWindow::

                void MainWindow::fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour) {
                

                and its said prototype for void Main...... does not match any in class 'MainWindow'

                kshegunovK Offline
                kshegunovK Offline
                kshegunov
                Moderators
                wrote on last edited by
                #38

                @Payx said in Picture:

                its said prototype for void Main...... does not match any in class 'MainWindow'

                They don't match, the compiler's correct.

                class MainWindow
                {
                    // ...
                    void fillSection();
                    // ...
                };
                

                in the header has different prototype from :

                void MainWindow::fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour)
                {
                    // ...
                

                in the source file. They must match, it's a requirement of the language.

                Read and abide by the Qt Code of Conduct

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                0
                • P Offline
                  P Offline
                  Payx
                  wrote on last edited by
                  #39

                  So where am i suppose to declare my functions ?

                  jsulmJ 1 Reply Last reply
                  0
                  • P Payx

                    So where am i suppose to declare my functions ?

                    jsulmJ Offline
                    jsulmJ Offline
                    jsulm
                    Lifetime Qt Champion
                    wrote on last edited by
                    #40

                    @Payx Again:

                    void fillSection()
                    

                    is NOT the same as

                    void fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour)
                    

                    So, either change void fillSection() to void fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour), or other way around. This is really basic C++.

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

                    1 Reply Last reply
                    1
                    • Pradeep KumarP Offline
                      Pradeep KumarP Offline
                      Pradeep Kumar
                      wrote on last edited by Pradeep Kumar
                      #41

                      Hi,

                      1. Function arguments must match otherwise u will get error.
                      2. Declare your functions in Header File, provide the definition in source file.
                      3. Use slots only when u want to get the values when signal is emitted providing the connect(); . Otherwise declare in any one of below specifiers.
                      4. add function in either of the access specifier depending upon your need

                      private:
                      void fillSection();

                      public:
                      void fillSection();

                      protected:
                      void fillSection();

                      The arguments which provided in declaration should match with the definition along with data type.

                      Thanks,

                      Pradeep Kumar
                      Qt,QML Developer

                      1 Reply Last reply
                      1
                      • P Offline
                        P Offline
                        Payx
                        wrote on last edited by Payx
                        #42

                        Thanks both of you, it works !
                        The problem i think is that i don't understand english very well, that's my problem.

                        So if i understood well,

                        i will have :

                        void MainWindow::on_push2_clicked()
                        {
                        
                        	QColor dominantColor(const QImage& pixi, const QPoint& topLeft, const QSize& rectSize);
                        	void fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour);
                        
                        }
                        

                        I check what the code do, if i'm right i have to define the
                        rectSize.height()
                        and rectSize.width()

                        and last question
                        when i have

                        for(int x = topLeft.x(); x < maxRight; ++x) {
                        		for(int y = topLeft.y(); x < maxBottom; ++x) {
                        

                        in the second line, it's not 'y' the variable who change?

                        and

                        const int maxRight = qMin(pixi.width(), topLeft.x() + rectSize.width());
                        for(int x = topLeft.x(); x < maxRight; ++x) {
                        

                        if we define rectSize (4*4) the for will go from 0 to 4 only no ? we need to change the rectsize at the end of the for no ?

                        VRoninV 1 Reply Last reply
                        0
                        • P Payx

                          Thanks both of you, it works !
                          The problem i think is that i don't understand english very well, that's my problem.

                          So if i understood well,

                          i will have :

                          void MainWindow::on_push2_clicked()
                          {
                          
                          	QColor dominantColor(const QImage& pixi, const QPoint& topLeft, const QSize& rectSize);
                          	void fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour);
                          
                          }
                          

                          I check what the code do, if i'm right i have to define the
                          rectSize.height()
                          and rectSize.width()

                          and last question
                          when i have

                          for(int x = topLeft.x(); x < maxRight; ++x) {
                          		for(int y = topLeft.y(); x < maxBottom; ++x) {
                          

                          in the second line, it's not 'y' the variable who change?

                          and

                          const int maxRight = qMin(pixi.width(), topLeft.x() + rectSize.width());
                          for(int x = topLeft.x(); x < maxRight; ++x) {
                          

                          if we define rectSize (4*4) the for will go from 0 to 4 only no ? we need to change the rectsize at the end of the for no ?

                          VRoninV Offline
                          VRoninV Offline
                          VRonin
                          wrote on last edited by
                          #43

                          @Payx said in Picture:

                          i will have :
                          void MainWindow::on_push2_clicked()
                          {

                          QColor dominantColor(const QImage& pixi, const QPoint& topLeft, const QSize& rectSize);
                          void fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour);

                          }

                          this makes no sense

                          in the second line, it's not 'y' the variable who change?

                          yes, I corrected it but @mrjj was faster and copied the code before I could amend it

                          the for will go from 0 to 4 only no ?

                          no, it will go from 0 to 3, 4 pixels

                          "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                          ~Napoleon Bonaparte

                          On a crusade to banish setIndexWidget() from the holy land of Qt

                          P kshegunovK 2 Replies Last reply
                          0
                          • VRoninV VRonin

                            @Payx said in Picture:

                            i will have :
                            void MainWindow::on_push2_clicked()
                            {

                            QColor dominantColor(const QImage& pixi, const QPoint& topLeft, const QSize& rectSize);
                            void fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour);

                            }

                            this makes no sense

                            in the second line, it's not 'y' the variable who change?

                            yes, I corrected it but @mrjj was faster and copied the code before I could amend it

                            the for will go from 0 to 4 only no ?

                            no, it will go from 0 to 3, 4 pixels

                            P Offline
                            P Offline
                            Payx
                            wrote on last edited by VRonin
                            #44

                            @VRonin

                            no, it will go from 0 to 3, 4 pixels

                            Yes but if my picture is composed by 500 pixels, it will go from 0 to 3 pixels, and thats it, so i have to increase at the end of my "for" no ?

                            this makes no sense

                            When i want to call a function i have to write :

                            fillSection();

                            but as i said i got an error.

                            so i change to fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour);

                            why this makes no sense?

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                            0
                            • VRoninV Offline
                              VRoninV Offline
                              VRonin
                              wrote on last edited by
                              #45

                              @Payx said in Picture:

                              Yes but if my picture is composed by 500 pixels, it will go from 0 to 3 pixels, and thats it, so i have to increase at the end of my "for" no ?

                              what would you do?

                              @Payx said in Picture:

                              why this makes no sense?

                              www.cplusplus.com/doc/tutorial/functions/

                              www.cplusplus.com/doc/tutorial/classes/

                              "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                              ~Napoleon Bonaparte

                              On a crusade to banish setIndexWidget() from the holy land of Qt

                              P 1 Reply Last reply
                              0
                              • VRoninV VRonin

                                @Payx said in Picture:

                                Yes but if my picture is composed by 500 pixels, it will go from 0 to 3 pixels, and thats it, so i have to increase at the end of my "for" no ?

                                what would you do?

                                @Payx said in Picture:

                                why this makes no sense?

                                www.cplusplus.com/doc/tutorial/functions/

                                www.cplusplus.com/doc/tutorial/classes/

                                P Offline
                                P Offline
                                Payx
                                wrote on last edited by Payx
                                #46

                                @VRonin I got rectSize = 4*4

                                the function will calculate the color in the rect 44, if my picture is 500500, i have to increase at the end of my "for" the rectSize.

                                like say that my maxRight isnt

                                qMin(pixi.width(), topLeft.x() + rectSize.width());
                                

                                anymore

                                and it's like qMin(pixi.width(), rectSize.width()+4)

                                and at the end of my for i will add a line to increase again and again the maxRight

                                1 Reply Last reply
                                0
                                • VRoninV Offline
                                  VRoninV Offline
                                  VRonin
                                  wrote on last edited by
                                  #47

                                  those to functions are designed to work on a single 4x4 area, you need to build something around them to make them work over the whole picture

                                  "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                                  ~Napoleon Bonaparte

                                  On a crusade to banish setIndexWidget() from the holy land of Qt

                                  1 Reply Last reply
                                  0
                                  • P Offline
                                    P Offline
                                    Payx
                                    wrote on last edited by
                                    #48

                                    Thanks for your link obviously what i need.

                                    so i replace : i got

                                    QColor dominantColor(pixi,point,size);
                                    

                                    and i define pixi as my image (in mainwindow.h)
                                    and QPoint point(0,0);
                                    and QSize size(4,4); thats correct ?

                                    but i block for the QColor in void fillSection(QImage& image, const QPoint& topLeft, const QSize& rectSize, const QColor& colour)

                                    1 Reply Last reply
                                    0
                                    • VRoninV VRonin

                                      @Payx said in Picture:

                                      i will have :
                                      void MainWindow::on_push2_clicked()
                                      {

                                      QColor dominantColor(const QImage& pixi, const QPoint& topLeft, const QSize& rectSize);
                                      void fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour);

                                      }

                                      this makes no sense

                                      in the second line, it's not 'y' the variable who change?

                                      yes, I corrected it but @mrjj was faster and copied the code before I could amend it

                                      the for will go from 0 to 4 only no ?

                                      no, it will go from 0 to 3, 4 pixels

                                      kshegunovK Offline
                                      kshegunovK Offline
                                      kshegunov
                                      Moderators
                                      wrote on last edited by kshegunov
                                      #49

                                      @VRonin said in Picture:

                                      @Payx said in Picture:

                                      i will have :

                                      void MainWindow::on_push2_clicked()
                                      {
                                         QColor dominantColor(const QImage& pixi, const QPoint& topLeft, const QSize& rectSize);
                                         void fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour);
                                      }
                                      

                                      this makes no sense

                                      It's valid C++, although highly unusual. Consider this:

                                      void userFunction1()
                                      {
                                          int x;
                                          testFunc(x);  //< Compile error: undeclared identifier testFunc
                                      }
                                      
                                      void userFunction2()
                                      {
                                          void testFunc(int &);
                                      
                                          int x;
                                          testFunc(x); //< We are okay
                                      }
                                      
                                      void testFunc(int & z)
                                      {
                                          z = 0;
                                      }
                                      

                                      C++ forbids function definitions to appear inside function bodies, but not declarations. On the other hand, class declarations and class definitions are valid inside functions, e.g.:

                                      void terribleToReadFunction()
                                      {
                                          struct  {
                                              int memberOfAnonymous() const
                                              {
                                                  return 0;
                                              }
                                          } inst;
                                      
                                          int z = inst.memberOfAnonymous(); //< z is 0
                                      }
                                      

                                      Read and abide by the Qt Code of Conduct

                                      P 1 Reply Last reply
                                      2
                                      • kshegunovK kshegunov

                                        @VRonin said in Picture:

                                        @Payx said in Picture:

                                        i will have :

                                        void MainWindow::on_push2_clicked()
                                        {
                                           QColor dominantColor(const QImage& pixi, const QPoint& topLeft, const QSize& rectSize);
                                           void fillSection(QImage& pixi, const QPoint& topLeft, const QSize& rectSize, const QColor& colour);
                                        }
                                        

                                        this makes no sense

                                        It's valid C++, although highly unusual. Consider this:

                                        void userFunction1()
                                        {
                                            int x;
                                            testFunc(x);  //< Compile error: undeclared identifier testFunc
                                        }
                                        
                                        void userFunction2()
                                        {
                                            void testFunc(int &);
                                        
                                            int x;
                                            testFunc(x); //< We are okay
                                        }
                                        
                                        void testFunc(int & z)
                                        {
                                            z = 0;
                                        }
                                        

                                        C++ forbids function definitions to appear inside function bodies, but not declarations. On the other hand, class declarations and class definitions are valid inside functions, e.g.:

                                        void terribleToReadFunction()
                                        {
                                            struct  {
                                                int memberOfAnonymous() const
                                                {
                                                    return 0;
                                                }
                                            } inst;
                                        
                                            int z = inst.memberOfAnonymous(); //< z is 0
                                        }
                                        
                                        P Offline
                                        P Offline
                                        Payx
                                        wrote on last edited by
                                        #50

                                        @kshegunov
                                        sorry i lost you

                                        in my

                                        void MainWindow::on_push2_clicked()
                                        {
                                        	QPoint point(0,0);
                                        	QSize size(4,4);
                                        	QColor dominantColor(pixi,point,size);
                                        
                                        }
                                        

                                        i try this i give what function needed and i declared point and size before

                                        mrjjM kshegunovK 2 Replies Last reply
                                        0
                                        • P Payx

                                          @kshegunov
                                          sorry i lost you

                                          in my

                                          void MainWindow::on_push2_clicked()
                                          {
                                          	QPoint point(0,0);
                                          	QSize size(4,4);
                                          	QColor dominantColor(pixi,point,size);
                                          
                                          }
                                          

                                          i try this i give what function needed and i declared point and size before

                                          mrjjM Offline
                                          mrjjM Offline
                                          mrjj
                                          Lifetime Qt Champion
                                          wrote on last edited by mrjj
                                          #51

                                          @Payx said in Picture:
                                          almost correct.

                                          void MainWindow::on_push2_clicked()
                                          {
                                          QPoint point(0,0);
                                          QSize size(4,4);
                                          QColor domicolor=dominantColor(pixi,point,size); // where does pixi come from? its in .h?

                                          }

                                          1 Reply Last reply
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