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Replacing image in QStyledItemDelegate

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  • G gabor53

    @raven-worx
    My original idea was that when the image field is chosen I replace the original image with a QPushbutton. When the button is clicked it opens QFile and lets the user choose a different picture. Than the icon in the view is changed to the new image and the new image is saved into the db.

    raven-worxR Offline
    raven-worxR Offline
    raven-worx
    Moderators
    wrote on last edited by
    #6

    @gabor53
    you can do this by creating a custom editor widget in createEditor(). Save the filepath (e.g. with setProperty("file-path")on the pushbutton, and read it again on save in setModelData(). In there you call model->setData().
    If not already done you of course need to implement setData() in your model to save the value (image,...) back to the DB.

    --- SUPPORT REQUESTS VIA CHAT WILL BE IGNORED ---
    If you have a question please use the forum so others can benefit from the solution in the future

    G 1 Reply Last reply
    2
    • raven-worxR raven-worx

      @gabor53
      you can do this by creating a custom editor widget in createEditor(). Save the filepath (e.g. with setProperty("file-path")on the pushbutton, and read it again on save in setModelData(). In there you call model->setData().
      If not already done you of course need to implement setData() in your model to save the value (image,...) back to the DB.

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

      @raven-worx
      I created the button in createEditor().

                  QPushButton *button = new QPushButton(parent) ;
                  button->setMaximumWidth (100);
      

      In setEditorData() I have

         QPushButton *button = qobject_cast<QPushButton*>(editor);
          if(button)
              {
                  button->setIcon (QIcon("C:/Programming/Projects/Folkfriends_1_0/icons/fix.png"));
              }
      

      .At this point I think I should have a button if the user clicks on the image but after clicking on the image I get a textEditor. What did I miss? Thank you.

      raven-worxR 1 Reply Last reply
      0
      • G gabor53

        @raven-worx
        I created the button in createEditor().

                    QPushButton *button = new QPushButton(parent) ;
                    button->setMaximumWidth (100);
        

        In setEditorData() I have

           QPushButton *button = qobject_cast<QPushButton*>(editor);
            if(button)
                {
                    button->setIcon (QIcon("C:/Programming/Projects/Folkfriends_1_0/icons/fix.png"));
                }
        

        .At this point I think I should have a button if the user clicks on the image but after clicking on the image I get a textEditor. What did I miss? Thank you.

        raven-worxR Offline
        raven-worxR Offline
        raven-worx
        Moderators
        wrote on last edited by
        #8

        @gabor53
        show the whole createEditor() method pls.

        --- SUPPORT REQUESTS VIA CHAT WILL BE IGNORED ---
        If you have a question please use the forum so others can benefit from the solution in the future

        G 2 Replies Last reply
        0
        • raven-worxR raven-worx

          @gabor53
          show the whole createEditor() method pls.

          G Offline
          G Offline
          gabor53
          wrote on last edited by
          #9

          @raven-worx
          I found the problem. The correct code is

           QPushButton *button = qobject_cast<QPushButton*>(editor);
              if(button)
                  {
                      button->setIcon (QIcon("C:/Programming/Projects/Folkfriends_1_0/icons/fix.png"));
          return button;
                  }
          

          I missed the return...

          raven-worxR 1 Reply Last reply
          0
          • raven-worxR raven-worx

            @gabor53
            show the whole createEditor() method pls.

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

            @raven-worx
            My next step (as I have the button now) is to place the original image on the button.
            In setEditorData I have the following:

            QPushButton *button = qobject_cast<QPushButton*>(editor);
                if(button)
                    {            
                        QPixmap buttonPix;
                        buttonPix.loadFromData (index.model ()->data (index,Qt::DisplayRole).toByteArray ());
            
                        qDebug() << "Fix image size: " << buttonPix.size();
            
                        button->setIcon (QIcon(buttonPix));
            
                    }
            

            I hoped to create a QPixmap from the BLOB in the database located where the index points. I wanted to place the pixmap on the button as an icon. The button is still there but the original image is not on the button and I also got the message
            Fix image size: QSize(0, 0)
            which shows my QPixmap is empty. What step did I miss? Thank you.

            1 Reply Last reply
            0
            • G gabor53

              @raven-worx
              I found the problem. The correct code is

               QPushButton *button = qobject_cast<QPushButton*>(editor);
                  if(button)
                      {
                          button->setIcon (QIcon("C:/Programming/Projects/Folkfriends_1_0/icons/fix.png"));
              return button;
                      }
              

              I missed the return...

              raven-worxR Offline
              raven-worxR Offline
              raven-worx
              Moderators
              wrote on last edited by
              #11

              @gabor53 said in Replacing image in QStyledItemDelegate:

              I missed the return...

              yes, i was suspecting that.

              @gabor53 said in Replacing image in QStyledItemDelegate:

              I hoped to create a QPixmap from the BLOB in the database located where the index points

              basically your code looks correct.
              Whats the image format of the image blob?
              Does your model's data() method really return a QByteArray for the Qt::DisplayRole?
              Please show your data() implementation.

              --- SUPPORT REQUESTS VIA CHAT WILL BE IGNORED ---
              If you have a question please use the forum so others can benefit from the solution in the future

              G 2 Replies Last reply
              0
              • raven-worxR raven-worx

                @gabor53 said in Replacing image in QStyledItemDelegate:

                I missed the return...

                yes, i was suspecting that.

                @gabor53 said in Replacing image in QStyledItemDelegate:

                I hoped to create a QPixmap from the BLOB in the database located where the index points

                basically your code looks correct.
                Whats the image format of the image blob?
                Does your model's data() method really return a QByteArray for the Qt::DisplayRole?
                Please show your data() implementation.

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

                @raven-worx
                The image format is jpg.
                I believe the model's data() method returns a QByteArray, but here is the code:
                The function that saves the image to the db:

                QFile fileReview(fileNameChosen);
                
                    if(fileReview.open (QIODevice::ReadOnly))
                        {
                            fileByteArray = fileReview.readAll ();
                        }
                
                QFile fileReview(fileNameChosen);
                
                    if(fileReview.open (QIODevice::ReadOnly))
                        {
                            fileByteArray = fileReview.readAll ();
                        }
                

                The model's data() implementation:

                 QStandardItemModel *fixModel = new QStandardItemModel(this);
                    ui->tableView_Fix->setModel (fixModel);
                
                    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 (13));
                
                            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);
                        }
                
                

                Thank you.

                1 Reply Last reply
                0
                • raven-worxR raven-worx

                  @gabor53 said in Replacing image in QStyledItemDelegate:

                  I missed the return...

                  yes, i was suspecting that.

                  @gabor53 said in Replacing image in QStyledItemDelegate:

                  I hoped to create a QPixmap from the BLOB in the database located where the index points

                  basically your code looks correct.
                  Whats the image format of the image blob?
                  Does your model's data() method really return a QByteArray for the Qt::DisplayRole?
                  Please show your data() implementation.

                  G Offline
                  G Offline
                  gabor53
                  wrote on last edited by
                  #13

                  @raven-worx
                  I also noticed, that for some reason all the images are saved 45 degrees turned right so all the vertical images are horizontal.

                  1 Reply Last reply
                  0
                  • G Offline
                    G Offline
                    gabor53
                    wrote on last edited by
                    #14

                    Ran the debugger and got the following at this line:

                         QPixmap buttonPix;
                                buttonPix.loadFromData (index.model ()->data (index,Qt::DisplayRole).toByteArray ());
                    

                    In the Locals and Expressions window I got the following Name - Value - Type values:
                    buttonPix - (invalid) - QPixmap.
                    I'm wondering why is it invalid? (Or what can make it invalid?)
                    Thank you.

                    raven-worxR 1 Reply Last reply
                    0
                    • G gabor53

                      Ran the debugger and got the following at this line:

                           QPixmap buttonPix;
                                  buttonPix.loadFromData (index.model ()->data (index,Qt::DisplayRole).toByteArray ());
                      

                      In the Locals and Expressions window I got the following Name - Value - Type values:
                      buttonPix - (invalid) - QPixmap.
                      I'm wondering why is it invalid? (Or what can make it invalid?)
                      Thank you.

                      raven-worxR Offline
                      raven-worxR Offline
                      raven-worx
                      Moderators
                      wrote on last edited by raven-worx
                      #15

                      @gabor53
                      you are already returning a QPixmap (fixModel->setData (fixModel->index (row1,3),fixPixmap,Qt::DecorationRole);) not a QByteArray

                      --- SUPPORT REQUESTS VIA CHAT WILL BE IGNORED ---
                      If you have a question please use the forum so others can benefit from the solution in the future

                      G 1 Reply Last reply
                      0
                      • raven-worxR raven-worx

                        @gabor53
                        you are already returning a QPixmap (fixModel->setData (fixModel->index (row1,3),fixPixmap,Qt::DecorationRole);) not a QByteArray

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

                        @raven-worx
                        I tried to use

                        buttonPix.loadFromData (index.model ()->data (index,Qt::DisplayRole).toByteArray ());
                        

                        without toByteArray() but it didn't work. I assumed that the model stores the data as a QVariant so I tried to do the following:

                        QPixmap buttonPix;
                                    QVariant pic;
                                    pic = (index.data (Qt::DisplayRole));
                                    buttonPix.loadFromData (pic.toByteArray());
                        
                                    button->setIcon (QIcon(buttonPix));
                        
                                    int row = index.row ();
                                    int col = index.column ();
                        
                                    qDebug() << "SetEditorData row, col: " << "(" << row << "," << col << ")";
                        
                                    qDebug() << "Fix image size: " << buttonPix.size();          
                        
                                    return;
                        
                        

                        and the message I got was identical to the previous one:
                        QPixmap::scaled: Pixmap is a null pixmap
                        SetEditorData row, col: ( 1 , 3 )
                        Fix image size: QSize(0, 0)

                        After running Debug at the

                          QPixmap buttonPix;
                        
                        

                        line the buttonPix value was buttonPix (481622520x389579424) QPixmap
                        which changed to buttonPix (Invalid) QPixmap at the QVariant pic line. What am I missing here? Is this a completely incorrect idea? Thank you.

                        1 Reply Last reply
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