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  • SGaistS SGaist

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

    P 離線
    P 離線
    Payx
    寫於 最後由 編輯
    #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 條回覆 最後回覆
    0
    • SGaistS 離線
      SGaistS 離線
      SGaist
      Lifetime Qt Champion
      寫於 最後由 編輯
      #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 條回覆 最後回覆
      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 離線
        kshegunovK 離線
        kshegunov
        Moderators
        寫於 最後由 編輯
        #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

        1 條回覆 最後回覆
        0
        • P 離線
          P 離線
          Payx
          寫於 最後由 編輯
          #39

          So where am i suppose to declare my functions ?

          jsulmJ 1 條回覆 最後回覆
          0
          • P Payx

            So where am i suppose to declare my functions ?

            jsulmJ 離線
            jsulmJ 離線
            jsulm
            Lifetime Qt Champion
            寫於 最後由 編輯
            #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 條回覆 最後回覆
            1
            • Pradeep KumarP 離線
              Pradeep KumarP 離線
              Pradeep Kumar
              寫於 最後由 Pradeep Kumar 編輯
              #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 條回覆 最後回覆
              1
              • P 離線
                P 離線
                Payx
                寫於 最後由 Payx 編輯
                #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 條回覆 最後回覆
                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 離線
                  VRoninV 離線
                  VRonin
                  寫於 最後由 編輯
                  #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 條回覆 最後回覆
                  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 離線
                    P 離線
                    Payx
                    寫於 最後由 VRonin 編輯
                    #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?

                    1 條回覆 最後回覆
                    0
                    • VRoninV 離線
                      VRoninV 離線
                      VRonin
                      寫於 最後由 編輯
                      #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 條回覆 最後回覆
                      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 離線
                        P 離線
                        Payx
                        寫於 最後由 Payx 編輯
                        #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 條回覆 最後回覆
                        0
                        • VRoninV 離線
                          VRoninV 離線
                          VRonin
                          寫於 最後由 編輯
                          #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 條回覆 最後回覆
                          0
                          • P 離線
                            P 離線
                            Payx
                            寫於 最後由 編輯
                            #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 條回覆 最後回覆
                            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 離線
                              kshegunovK 離線
                              kshegunov
                              Moderators
                              寫於 最後由 kshegunov 編輯
                              #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 條回覆 最後回覆
                              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 離線
                                P 離線
                                Payx
                                寫於 最後由 編輯
                                #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 條回覆 最後回覆
                                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 離線
                                  mrjjM 離線
                                  mrjj
                                  Lifetime Qt Champion
                                  寫於 最後由 mrjj 編輯
                                  #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 條回覆 最後回覆
                                  2
                                  • 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

                                    kshegunovK 離線
                                    kshegunovK 離線
                                    kshegunov
                                    Moderators
                                    寫於 最後由 編輯
                                    #52

                                    @Payx said in Picture:

                                    sorry i lost you

                                    No, it's me who lost you. I was commenting on @VRonin's remark about your code. However, this:

                                    QColor dominantColor(pixi,point,size);
                                    

                                    is neither a function call, nor is it a function declaration. The compiler will interpret this as a variable and will throw "unknown conversion from type X to type Y" errors. You should carefully read @VRonin's link on functions - what is a declaration, what is a definition and how to put it all together. Otherwise you are in for a terrible time, Qt or otherwise.

                                    Kind regards.

                                    Read and abide by the Qt Code of Conduct

                                    1 條回覆 最後回覆
                                    2
                                    • P 離線
                                      P 離線
                                      Payx
                                      寫於 最後由 編輯
                                      #53

                                      I have to declare my function,
                                      say what they do
                                      and call it.

                                      I say in my .cpp what she does :

                                      QColor dominantColor(const QImage& image, const QPoint& topLeft, const QSize& rectSize) {
                                      // calculate start stop values for the rect
                                      	 const int maxRight = qMin(image.width(), topLeft.x() + rectSize.width());
                                      	const int maxBottom = qMin(image.height(), topLeft.y() + rectSize.height());
                                      	QVector<QColor> coloursList; // this is a list of all colors seen!
                                      	for(int x = topLeft.x(); x < maxRight; ++x) {
                                      		for(int y = topLeft.y(); y < maxBottom; ++y) {
                                      			coloursList << image.pixelColor(x, y); // store all colors seen in this Rect
                                      		}
                                      	}
                                      
                                      	// these are functions that count (accumulate) how many times RED, GREEN and blue been used ( using the list from before)
                                      	const qint64 sumRed = std::accumulate(coloursList.constBegin(), coloursList.constEnd(), 0, [](qint64 strt,  const QColor & val)->qint64 {return strt + val.red();});
                                      	const qint64 sumGreen = std::accumulate(coloursList.constBegin(), coloursList.constEnd(), 0, [](qint64 strt, const QColor & val)->qint64 {return strt + val.green();});
                                      	const qint64 sumBlue = std::accumulate(coloursList.constBegin(), coloursList.constEnd(), 0, [](qint64 strt, const QColor & val)->qint64 {return strt + val.blue();});
                                      	// now we check out which is most used
                                      	if(sumRed >= sumGreen  && sumRed >= sumBlue)
                                      		return Qt::red;
                                      	if(sumGreen  >= sumBlue)
                                      		return Qt::green;
                                      	return Qt::blue;
                                      }
                                      

                                      I call her and i stock the result in a QColor

                                      void MainWindow::on_push2_clicked()
                                      {
                                      	QPoint point(0,0);
                                      	QSize size(4,4);
                                      	QColor domicolor=dominantColor(pixi,point,size);
                                      // pixi is my image declared in .h with QImage pixi;
                                      
                                      }
                                      

                                      the problem that i dont know where i can declare her. I try every possibilities

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                                      0
                                      • VRoninV 離線
                                        VRoninV 離線
                                        VRonin
                                        寫於 最後由 編輯
                                        #54

                                        ok, now we are making progress. you got what the dominant colour is, now you have to paint the rectange

                                        "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 條回覆 最後回覆
                                        2
                                        • P 離線
                                          P 離線
                                          Payx
                                          寫於 最後由 編輯
                                          #55

                                          @VRonin said in Picture:

                                          ok, now we are making progress. you got what the dominant colour is, now you have to paint the rectange

                                          sorry if don't listen to you very well but

                                          it say that my function isnt declared (dominantColor)

                                          1 條回覆 最後回覆
                                          0

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