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Query dispays memory address instead of variable value

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queryqstandarditemmodel
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  • G Offline
    G Offline
    gabor53
    wrote on last edited by
    #1

    Hi
    I use the following code to display data and an image from a db:

    #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 (ID = query.value (0).toInt ());
            qDebug() << "ID = " << Item;
            smodel->setItem (0,0,Item);
    
            QByteArray ByteArray;
            ByteArray = query.value (1).toByteArray ();
            QPixmap Pixmap = QPixmap();
    		Pixmap.loadFromData (ByteArray);
    
    
            Item2->setData (QVariant(Pixmap),Qt::DecorationRole);
    
    		smodel->setItem (0,1,Item2);
    
            ui->tableView->setModel (smodel);
    
    db.close ();
    
    }
    
    MainWindow::~MainWindow()
    {
        delete ui;
    }
    
    

    When I run it I get the following messages in Application Output:

    Starting C:\Programming\Qtsamples\build-Image_from_db_to_Table-Desktop_Qt_5_5_0_Static_MinGW_32_bit-Release\release\Image_from_db_to_Table.exe...
    The database is open!
    The query is active.
    ID = 0x29fd30
    C:\Programming\Qtsamples\build-Image_from_db_to_Table-Desktop_Qt_5_5_0_Static_MinGW_32_bit-Release\release\Image_from_db_to_Table.exe exited with code 0.

    What am I doing incorrectly? The ID should be 1 and I assume the memory address is displayed.
    I appreciate any help. Thank you.

    1 Reply Last reply
    0
    • dheerendraD Offline
      dheerendraD Offline
      dheerendra
      Qt Champions 2022
      wrote on last edited by
      #2

      Do something like this.

      qDebug() << "ID = " << Item->data().toInt();
      

      Dheerendra
      @Community Service
      Certified Qt Specialist
      http://www.pthinks.com

      1 Reply Last reply
      4
      • G Offline
        G Offline
        gabor53
        wrote on last edited by
        #3

        Thank you. That worked.
        I've noticed that I get no error message, but it displays nothing in the ID column. What did I do wrong there/
        Thank you.

        1 Reply Last reply
        0
        • Chris KawaC Offline
          Chris KawaC Offline
          Chris Kawa
          Lifetime Qt Champion
          wrote on last edited by
          #4

          You're setting the wrong role. See my answer here.

          1 Reply Last reply
          1

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