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Overloaded function type error

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  • G gabor53

    @artwaw
    In the .h file I have

    QByteArray imageArray;
    
      QString imageFile;
      void addNewImage(QString imageFile) const;
    
    

    and in the cpp file I have

    if(newImage.open (QIODevice::ReadOnly)) {
        imageArray = newImage.readAll();
      }
    
      QSqlQuery querys(db);
    
      if(!db.open ())
    
      {
        qDebug() << "The database is not open (submit)!";
      } else {
        qDebug() << "The database is open (submit)!";
      }
    //Get Id from somewhere
      querys.prepare("INSERT INTO Items (ID, Pic) VALUES(:ID, :Pic)" );
      querys.bindValue (":ID", sIDReview);
    }
    
    

    It still gives me the error message
    C:\Programming\Projects\Folkfriends_bzr\trunk\imagedelegate.cpp:44: error: passing 'const QByteArray' as 'this' argument discards qualifiers [-fpermissive]
    imageArray = newImage.readAll();
    ^

    Thank you for your help.

    artwawA Offline
    artwawA Offline
    artwaw
    wrote on last edited by
    #6

    @gabor53
    Why have you void addNewImage(QString imageFile) const;? Please try to remove const at the end.

    For more information please re-read.

    Kind Regards,
    Artur

    G 1 Reply Last reply
    1
    • artwawA artwaw

      @gabor53
      Why have you void addNewImage(QString imageFile) const;? Please try to remove const at the end.

      G Offline
      G Offline
      gabor53
      wrote on last edited by gabor53
      #7

      Artur,
      Now it gives a new error message:
      C:\Programming\Projects\Folkfriends_bzr\trunk\imagedelegate.cpp:30: error: passing 'const ImageDelegate' as 'this' argument discards qualifiers [-fpermissive]
      addNewImage (imageFile);
      ^

      My imagedelegate.h:

       void addNewImage(QString imageFile);
      

      the call in imagedelegate.cpp:

      void ImageDelegate::setModelData(QWidget* editor, QAbstractItemModel* model, const QModelIndex& index) const {
        ImagePickButton* imgPick = qobject_cast<ImagePickButton*>(editor);
        Q_ASSERT(imgPick);
      
        if(imgPick->selectedFile().isEmpty()) {
          model->setData(index, QVariant(), Qt::UserRole);
          model->setData(index, QVariant(), Qt::DecorationRole);
        } else {
          model->setData(index, imgPick->selectedFile(), Qt::UserRole);
          model->setData(index, QIcon(imgPick->selectedFile()), Qt::DecorationRole);
        }
        addNewImage (imageFile);
      }
      

      (this causes the error)

      and the function

      oid ImageDelegate::addNewImage(QString imageFile) {
        qDebug() << "Entered addNewImage";
      
        QFile newImage(imageFile);
      
        if(newImage.open (QIODevice::ReadOnly)) {
          imageArray = newImage.readAll();
        }
      
        QSqlQuery querys(db);
      
        if(!db.open ())
      
        {
          qDebug() << "The database is not open (submit)!";
        } else {
          qDebug() << "The database is open (submit)!";
        }
      //Get Id from somewhere
        querys.prepare("INSERT INTO Items (ID, Pic) VALUES(:ID, :Pic)" );
        querys.bindValue (":ID", sIDReview);
      }
      
      

      Thank you for your help.

      jsulmJ 1 Reply Last reply
      0
      • G gabor53

        Artur,
        Now it gives a new error message:
        C:\Programming\Projects\Folkfriends_bzr\trunk\imagedelegate.cpp:30: error: passing 'const ImageDelegate' as 'this' argument discards qualifiers [-fpermissive]
        addNewImage (imageFile);
        ^

        My imagedelegate.h:

         void addNewImage(QString imageFile);
        

        the call in imagedelegate.cpp:

        void ImageDelegate::setModelData(QWidget* editor, QAbstractItemModel* model, const QModelIndex& index) const {
          ImagePickButton* imgPick = qobject_cast<ImagePickButton*>(editor);
          Q_ASSERT(imgPick);
        
          if(imgPick->selectedFile().isEmpty()) {
            model->setData(index, QVariant(), Qt::UserRole);
            model->setData(index, QVariant(), Qt::DecorationRole);
          } else {
            model->setData(index, imgPick->selectedFile(), Qt::UserRole);
            model->setData(index, QIcon(imgPick->selectedFile()), Qt::DecorationRole);
          }
          addNewImage (imageFile);
        }
        

        (this causes the error)

        and the function

        oid ImageDelegate::addNewImage(QString imageFile) {
          qDebug() << "Entered addNewImage";
        
          QFile newImage(imageFile);
        
          if(newImage.open (QIODevice::ReadOnly)) {
            imageArray = newImage.readAll();
          }
        
          QSqlQuery querys(db);
        
          if(!db.open ())
        
          {
            qDebug() << "The database is not open (submit)!";
          } else {
            qDebug() << "The database is open (submit)!";
          }
        //Get Id from somewhere
          querys.prepare("INSERT INTO Items (ID, Pic) VALUES(:ID, :Pic)" );
          querys.bindValue (":ID", sIDReview);
        }
        
        

        Thank you for your help.

        jsulmJ Offline
        jsulmJ Offline
        jsulm
        Lifetime Qt Champion
        wrote on last edited by
        #8

        @gabor53 Why is ImageDelegate::setModelData const?!
        Only methods which do not change the STATE of the object are allowed to be const.
        And you cannot call non const methods in const methods.
        So, remove the const from ImageDelegate::setModelData...

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

        1 Reply Last reply
        0
        • SGaistS Offline
          SGaistS Offline
          SGaist
          Lifetime Qt Champion
          wrote on last edited by
          #9

          @jsulm In this case, setModelData should stay const, it's the original method signature. addNewImage should be made const (and its parameter a const reference). And also, why not use the model directly to store the new data ?

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

          G 1 Reply Last reply
          0
          • SGaistS SGaist

            @jsulm In this case, setModelData should stay const, it's the original method signature. addNewImage should be made const (and its parameter a const reference). And also, why not use the model directly to store the new data ?

            G Offline
            G Offline
            gabor53
            wrote on last edited by
            #10

            @SGaist
            Is there an example how to do it? I have 2 data types: image and text. If there is a way to let the model store the data and update the db instead of my delegate that would save a lot of coding.
            Thank you.

            1 Reply Last reply
            0
            • SGaistS Offline
              SGaistS Offline
              SGaist
              Lifetime Qt Champion
              wrote on last edited by
              #11

              Can you give a more complete description of what you are trying to achieve ?

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

              G 1 Reply Last reply
              0
              • SGaistS SGaist

                Can you give a more complete description of what you are trying to achieve ?

                G Offline
                G Offline
                gabor53
                wrote on last edited by
                #12

                @SGaist
                This part displays the DB data in a table view where the user can review and correct data. Some of the fields are corrected as text fields, some of them as drop downs and I also have an image field. That's why I have the mydelegate and image delegate classes to handle the different editors. My struggle is to pass the image file name to a function where the corrected image can be saved to the DB replacing the old, incorrect image.
                The problem is that the original delegate functions are const functions and as I most likely incorrectly handle them I keep getting different error messages.
                Thank you for your help.

                1 Reply Last reply
                0
                • SGaistS Offline
                  SGaistS Offline
                  SGaist
                  Lifetime Qt Champion
                  wrote on last edited by
                  #13

                  Then there's no need for a "do-it-all" delegate.

                  Assign your delegate only to the column where it make sense. That will simplify your life.

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

                  G 1 Reply Last reply
                  0
                  • SGaistS SGaist

                    Then there's no need for a "do-it-all" delegate.

                    Assign your delegate only to the column where it make sense. That will simplify your life.

                    G Offline
                    G Offline
                    gabor53
                    wrote on last edited by
                    #14

                    @SGaist
                    Which is the better: to have a separate delegate for each column where needed or have one delegate for each type of input method ? (For example one delegate handles all dropdowns, one all check idea etc.)
                    Thank you.

                    1 Reply Last reply
                    0
                    • SGaistS Offline
                      SGaistS Offline
                      SGaist
                      Lifetime Qt Champion
                      wrote on last edited by
                      #15

                      You only need as many delegate as you have special cases.

                      Note that I didn't say "as many as the column count". If you have several columns of a special type then juste instantiate one delegate per column.

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

                      G 1 Reply Last reply
                      0
                      • SGaistS SGaist

                        You only need as many delegate as you have special cases.

                        Note that I didn't say "as many as the column count". If you have several columns of a special type then juste instantiate one delegate per column.

                        G Offline
                        G Offline
                        gabor53
                        wrote on last edited by
                        #16

                        @SGaist
                        How can I use the model directly to save the newly picked image? Is there a sample code you know about?

                        1 Reply Last reply
                        0
                        • SGaistS Offline
                          SGaistS Offline
                          SGaist
                          Lifetime Qt Champion
                          wrote on last edited by
                          #17

                          Well, you have a pointer to your model in setModelData, so why not use it ?

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

                          G 1 Reply Last reply
                          0
                          • SGaistS SGaist

                            Well, you have a pointer to your model in setModelData, so why not use it ?

                            G Offline
                            G Offline
                            gabor53
                            wrote on last edited by
                            #18

                            @SGaist
                            I started to use the pointer in setModelData. Added

                            oid ImageDelegate::setModelData(QWidget* editor, QAbstractItemModel* model, const QModelIndex& index) const {
                              ImagePickButton* imgPick = qobject_cast<ImagePickButton*>(editor);
                              Q_ASSERT(imgPick);
                            
                              if(imgPick->selectedFile().isEmpty()) {
                                model->setData(index, QVariant(), Qt::UserRole);
                                model->setData(index, QVariant(), Qt::DecorationRole);
                              } else {
                                model->setData(index, imgPick->selectedFile(), Qt::UserRole);
                                model->setData(index, QIcon(imgPick->selectedFile()), Qt::DecorationRole);
                                //Adding image to db
                            
                                qDebug() << "Selected file: " << imgPick->selectedFile();
                                qDebug() << "Selected file name: " << imgPick->m_selectedFile;
                            //new
                                model->setData (index, imgPick->selectedFile (), Qt::DecorationRole);
                              }
                            

                            Causes no error, but doesn't save the img to the db ether. What am I supposed to use to commit the changes to the db?

                            1 Reply Last reply
                            0
                            • SGaistS Offline
                              SGaistS Offline
                              SGaist
                              Lifetime Qt Champion
                              wrote on last edited by
                              #19

                              What kind of model are you using ?

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

                              G 1 Reply Last reply
                              0
                              • SGaistS SGaist

                                What kind of model are you using ?

                                G Offline
                                G Offline
                                gabor53
                                wrote on last edited by
                                #20

                                @SGaist
                                I use QStandardItemModel.

                                #include "fixdb.h"
                                #include "ui_fixdb.h"
                                #include <QDebug>
                                
                                FixDb::FixDb(QWidget* parent) :
                                  QDialog(parent),
                                  ui(new Ui::FixDb) {
                                  ui->setupUi(this);
                                
                                  correctFriend ();
                                }
                                
                                FixDb::~FixDb() {
                                  delete ui;
                                }
                                
                                void FixDb::correctFriend() {
                                  QSqlQuery query_fix ("SELECT * FROM Items ORDER BY name asc");
                                
                                  if(query_fix.isActive () == true) {
                                    qDebug() << "The query_fix is active!";
                                  } else {
                                    qDebug() << "The query_fix is NOT active!" << query_fix.lastError ();
                                  }
                                
                                  QStandardItemModel* fixModel = new QStandardItemModel(this);
                                  ui->tableView_Fix->setModel (fixModel);
                                
                                
                                  ui->tableView_Fix->setItemDelegateForColumn(3, new ImageDelegate(this));
                                
                                
                                  for(int row1 = 0; query_fix.next (); row1++) {
                                    if(row1 == 0) {
                                      const QSqlRecord qRec = query_fix.record();
                                      qDebug() << "The number of records (MainWindow): " << qRec;
                                      fixModel->insertColumns (0, qRec.count());
                                      qDebug() << "fixdb record count: " << qRec.count ();
                                
                                    }
                                
                                    fixModel->insertRow (row1);
                                    fixModel->setData (fixModel->index (row1, 0), query_fix.value (0));
                                    fixModel->setData (fixModel->index (row1, 1), query_fix.value (1));
                                    fixModel->setData (fixModel->index (row1, 2), query_fix.value (11));
                                
                                    fixPixmap.loadFromData (query_fix.value (2).toByteArray ());
                                    fixPixmap = fixPixmap.scaled (100, 100, Qt::KeepAspectRatio);
                                
                                    fixModel->setData (fixModel->index (row1, 3), fixPixmap, Qt::DecorationRole);
                                    fixModel->setData (fixModel->index (row1, 4), query_fix.value (11));
                                    fixModel->setData (fixModel->index (row1, 5), query_fix.value (10));
                                    fixModel->setData (fixModel->index (row1, 6), query_fix.value (3));
                                    fixModel->setData (fixModel->index(row1, 7), query_fix.value (4));
                                    fixModel->setData (fixModel->index (row1, 8), query_fix.value (12));
                                    fixModel->setData (fixModel->index (row1, 9), query_fix.value (7));
                                    fixModel->setData (fixModel->index (row1, 10), query_fix.value (8));
                                    fixModel->setData (fixModel->index (row1, 11), query_fix.value (9));
                                
                                    ui->tableView_Fix->setRowHeight (row1, 100);
                                  }
                                
                                  ui->tableView_Fix->horizontalHeader ()->setStyleSheet ("QHeaderView{font: 14pt Arial; color: blue; font-weight: bold; text-decoration: underline;}");
                                  ui->tableView_Fix->verticalHeader ()->setVisible (false);
                                  ui->tableView_Fix->setAlternatingRowColors (true);
                                  ui->tableView_Fix->setStyleSheet ("alternate-background-color: rgb(224,255,248); background-color: white; font: 14pt Arial; ");
                                
                                  fixModel->setHeaderData (0, Qt::Horizontal, QObject::tr ("ID"));
                                  fixModel->setHeaderData (1, Qt::Horizontal, QObject::tr ("Name"));
                                  fixModel->setHeaderData (2, Qt::Horizontal, QObject::tr ("What"));
                                  fixModel->setHeaderData (3, Qt::Horizontal, QObject::tr ("Image"));
                                  fixModel->setHeaderData (4, Qt::Horizontal, QObject::tr ("Material"));
                                  fixModel->setHeaderData (5, Qt::Horizontal, QObject::tr ("Color"));
                                  fixModel->setHeaderData (6, Qt::Horizontal, QObject::tr ("Description"));
                                  fixModel->setHeaderData (7, Qt::Horizontal, QObject::tr ("Adoption Date"));
                                  fixModel->setHeaderData (8, Qt::Horizontal, QObject::tr ("Signed by"));
                                  fixModel->setHeaderData (9, Qt::Horizontal, QObject::tr ("History"));
                                  fixModel->setHeaderData (10, Qt::Horizontal, QObject::tr ("Age"));
                                  fixModel->setHeaderData (11, Qt::Horizontal, QObject::tr ("Notes"));
                                
                                  ui->tableView_Fix->setColumnWidth (0, 60);
                                  ui->tableView_Fix->setColumnWidth (1, 120);
                                  ui->tableView_Fix->setColumnWidth (2, 150);
                                  ui->tableView_Fix->setColumnWidth (3, 100);
                                  ui->tableView_Fix->setColumnWidth (4, 130);
                                  ui->tableView_Fix->setColumnWidth (5, 120);
                                  ui->tableView_Fix->setColumnWidth (6, 400);
                                  ui->tableView_Fix->setColumnWidth (7, 150);
                                  ui->tableView_Fix->setColumnWidth (8, 200);
                                  ui->tableView_Fix->setColumnWidth (9, 400);
                                  ui->tableView_Fix->setColumnWidth (10, 130);
                                  ui->tableView_Fix->setColumnWidth (11, 300);
                                
                                  ui->tableView_Fix->setWordWrap (true);
                                
                                
                                }
                                
                                
                                1 Reply Last reply
                                0
                                • SGaistS Offline
                                  SGaistS Offline
                                  SGaist
                                  Lifetime Qt Champion
                                  wrote on last edited by
                                  #21

                                  Why not use a QSqlTableModel ?

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

                                  G 1 Reply Last reply
                                  0
                                  • SGaistS SGaist

                                    Why not use a QSqlTableModel ?

                                    G Offline
                                    G Offline
                                    gabor53
                                    wrote on last edited by
                                    #22

                                    @SGaist
                                    I had difficulties with the elegates. Can I still use different delegates for some columns? If so I will redo that section.

                                    1 Reply Last reply
                                    0
                                    • SGaistS Offline
                                      SGaistS Offline
                                      SGaist
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #23

                                      Yes, you can.

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

                                      G 1 Reply Last reply
                                      1
                                      • SGaistS SGaist

                                        Yes, you can.

                                        G Offline
                                        G Offline
                                        gabor53
                                        wrote on last edited by
                                        #24

                                        @SGaist
                                        Thank you.
                                        I'm working on it.

                                        1 Reply Last reply
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