Resizing image to display in TableView



  • Hi,
    I'm trying to resize an image pulled from a database to be able to display it in TableView.

    #include "mainwindow.h"
    #include "ui_mainwindow.h"
    
    MainWindow::MainWindow(QWidget *parent) :
        QMainWindow(parent),
        ui(new Ui::MainWindow)
    {
        ui->setupUi(this);
        QSqlDatabase db;
            db = QSqlDatabase::addDatabase ("QSQLITE");
            db.setDatabaseName ("C:/Programming/Qtsamples/Image_from_db_to_Table/db.db");
    
            if(!db.open ())
            {
                qDebug() << "The database is NOT open!";
            }
            else
            {
                qDebug() << "The database is open!";
            }
    
            QSqlQuery query("SELECT ID,Pic FROM Items");
    
            if(query.isActive()==true)
              {
                  qDebug() << "The query is active.";
              }
              else
              {
                 qDebug() << "The query is NOT active.";
              } 
    
            query.first ();
           	int ID;
    
            QStandardItemModel *smodel = new QStandardItemModel;
            QStandardItem *Item = new QStandardItem();
            QStandardItem *Item2 = new QStandardItem();
    
            Item->setData (QVariant(ID = query.value (0).toInt ()));
            qDebug() << "ID = " << Item->data ().toInt ();
            smodel->setItem (0,0,Item);
    
            QByteArray ByteArray;
            ByteArray = query.value (1).toByteArray ();
         	QPixmap Pixmap;
    
    		Pixmap.loadFromData (ByteArray);
    
    		Pixmap.scaled (100,100,Qt::KeepAspectRatio);
    
            Item2->setData (QVariant(Pixmap),Qt::DecorationRole);
    
    		smodel->setItem (0,1,Item2);
            ui->tableView->verticalHeader ()->setDefaultSectionSize (100);
            ui->tableView->horizontalHeader ()->setDefaultSectionSize (100);
    
            ui->tableView->setModel (smodel);
    
    db.close ();
    
    }
    
    MainWindow::~MainWindow()
    {
        delete ui;
    }
    

    It displays the image but without resizing. What can I do differently to be able to see the whole image?
    Thank you.



  • May be you can try this

     Pixmap.scaled (100,100 Qt::IgnoreAspectRatio, Qt::FastTransformation));

  • Qt Champions 2016

    Hi
    The scaled function returns the modified version
    not changing the original one.
    so
    Pixmap.scaled (100,100,Qt::KeepAspectRatio);
    should be
    Pixmap=Pixmap.scaled (100,100,Qt::KeepAspectRatio);
    or
    QPixmap myscaled=Pixmap.scaled (100,100,Qt::KeepAspectRatio);
    If you want to use the scaled version later on.

    http://doc.qt.io/qt-5.5/qpixmap.html#scaled



  • Thank you. It worked.


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