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QStandardItemModel doesn't display data

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  • Pradeep KumarP Offline
    Pradeep KumarP Offline
    Pradeep Kumar
    wrote on last edited by Pradeep Kumar
    #9

    void FixDb::correctFriend()
    {
    qDebug() << "Entered 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);
fixmodel->setHeaderData (0,Qt::Horizontal, QObject::tr("ID"));
fixmodel->setHeaderData (1,Qt::Horizontal, QObject::tr("Name"));
fixmodel->setHeaderData (2,Qt::Horizontal, QObject::tr("What is the Friend?"));
fixmodel->setHeaderData (3,Qt::Horizontal, QObject::tr("The Friend's Picture"));
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"));
fixmodel->setColumnCount(12);		// as per your column header its 11							
	
ui->tableView_fix->horizontalHeader ()->setStyleSheet ("QHeaderView{font: 14pt Arial; color: blue; font-weight: bold;}");
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");
ui->tableView_fix->setEditTriggers (QAbstractItemView::CurrentChanged);

ui->tableView_fix->setColumnWidth (0,100);
ui->tableView_fix->setColumnWidth (1,200);
ui->tableView_fix->setColumnWidth (2,200);
ui->tableView_fix->setColumnWidth (3,90);
ui->tableView_fix->setColumnWidth (4,200);
ui->tableView_fix->setColumnWidth (5,200);
ui->tableView_fix->setColumnWidth (6,350);
ui->tableView_fix->setColumnWidth (7,200);
ui->tableView_fix->setColumnWidth (8,200);
ui->tableView_fix->setColumnWidth (9,350);
ui->tableView_fix->setColumnWidth (10,200);
ui->tableView_fix->setColumnWidth (11,350);
ui->tableView_fix->setWordWrap (true);


for(int row1 = 0; query_fix.next(); ++row1)
    {
 fixmodel->setRowCount(row1);
 fixmodel->setData (fixmodel->index(row1,0),query_fix.value (0).toString());			// oth column value
 fixmodel->setData (fixmodel->index(row1,1),query_fix.value (1).toString ());			// 1th column value	
fixmodel->setData (fixmodel->index(row1,2),query_fix.value (13).toString ());			// 13th column value

 fixPixmap.loadFromData (query_fix.value (2).toByteArray ());					// 2th column value	
 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).toString ());			// 11th column value	
fixmodel->setData (fixmodel->index(row1,5),query_fix.value (10).toString ());			// 10th column value	
 fixmodel->setData (fixmodel->index(row1,6),query_fix.value (3).toString ());			// 3th column value

        monthf = query_fix.value (4).toString ();								// 4th column value
        dayf = query_fix.value (5).toString ();								// 5th column value	
        yearf = query_fix.value (6).toString ();								// 6th column value
        date = monthf + "/" + dayf + "/" + yearf;	

fixmodel->setData (fixmodel->index(row1,5),date);
fixmodel->setData (fixmodel->index(row1,6),query_fix.value (12).toString ());			// 12th column value
fixmodel->setData (fixmodel->index(row1,7),query_fix.value (7).toString ());			// 7th column value
fixmodel->setData (fixmodel->index(row1,8),query_fix.value (8).toString ());			// 8th column value	
fixmodel->setData (fixmodel->index(row1,9),query_fix.value (9).toString ());			// 9th column value

 ui->tableView_fix->setRowHeight (row1,100);
    }


ui->tableView_fix->setModel (fixmodel);

    }

    Pradeep Kumar
    Qt,QML Developer

    1 Reply Last reply
    1
    • Pradeep KumarP Offline
      Pradeep KumarP Offline
      Pradeep Kumar
      wrote on last edited by Pradeep Kumar
      #10

      As @SGaist said u need to specify Columncount and rowcount.

      fixmodel->setData (fixmodel->index(row1,5),query_fix.value (10).toString ());

      fixmodel->setData (fixmodel->index(row1,5),date);

      Are u trying to insert different values in same column?.

      Pradeep Kumar
      Qt,QML Developer

      1 Reply Last reply
      3
      • VRoninV Offline
        VRoninV Offline
        VRonin
        wrote on last edited by VRonin
        #11

        EDIT, sorry, this is a duplicate of @SGaist 's answer

        you are never adding the columns...

        for(int row1 = 1; query_fix.next (); row1++)
        {
            if(row1 == 0)

        row1 is never 0

        "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

        G 1 Reply Last reply
        1
        • VRoninV VRonin

          EDIT, sorry, this is a duplicate of @SGaist 's answer

          you are never adding the columns...

          for(int row1 = 1; query_fix.next (); row1++)
        {
            if(row1 == 0)

          row1 is never 0

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

          @VRonin
          Hi,
          I rewrote a few things. As a result it displays data:

          void FixDb::correctFriend()
{
    qDebug() << "Entered 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);


    const QSqlRecord qR = query_fix.record ();
    qDebug() << "The number of records: " << qR;
    fixmodel->insertColumns (0, qR.count());

    for(int row1 = 0; query_fix.next (); row1++)
        {
            fixmodel->insertRow (row1);
            fixmodel->setData (fixmodel->index(row1,0),query_fix.value (0).toString ());
            fixmodel->setData (fixmodel->index(row1,1),query_fix.value (1).toString ());
            fixmodel->setData (fixmodel->index(row1,2),query_fix.value (13).toString ());

            qDebug() << "ID in fix: " << query_fix.value (0).toString ();

            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).toString ());
            fixmodel->setData (fixmodel->index(row1,5),query_fix.value (10).toString ());
            fixmodel->setData (fixmodel->index(row1,6),query_fix.value (3).toString ());

            monthf = query_fix.value (4).toString ();
            dayf = query_fix.value (5).toString ();
            yearf = query_fix.value (6).toString ();
            date = monthf + "/" + dayf + "/" + yearf;

            fixmodel->setData (fixmodel->index(row1,7),date);
            fixmodel->setData (fixmodel->index(row1,8),query_fix.value (12).toString ());
            fixmodel->setData (fixmodel->index(row1,9),query_fix.value (7).toString ());
            fixmodel->setData (fixmodel->index(row1,10),query_fix.value (8).toString ());
            fixmodel->setData (fixmodel->index(row1,11),query_fix.value (9).toString ());
            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");
            ui->tableView_fix->setEditTriggers (QAbstractItemView::CurrentChanged);
            fixmodel->setHeaderData (0,Qt::Horizontal, QObject::tr("ID"));
            fixmodel->setHeaderData (1,Qt::Horizontal, QObject::tr("Name"));
            fixmodel->setHeaderData (2,Qt::Horizontal, QObject::tr("What is the Friend?"));
            fixmodel->setHeaderData (3,Qt::Horizontal, QObject::tr("Picture"));
            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 (0,1);
            ui->tableView_fix->setColumnWidth (1,200);
            ui->tableView_fix->setColumnWidth (2,200);
            ui->tableView_fix->setColumnWidth (3,90);
            ui->tableView_fix->setColumnWidth (4,200);
            ui->tableView_fix->setColumnWidth (5,200);
            ui->tableView_fix->setColumnWidth (6,350);
            ui->tableView_fix->setColumnWidth (7,200);
            ui->tableView_fix->setColumnWidth (8,200);
            ui->tableView_fix->setColumnWidth (9,350);
            ui->tableView_fix->setColumnWidth (10,200);
            ui->tableView_fix->setColumnWidth (11,350);

            ui->tableView_fix->setWordWrap (true);

            ui->tableView_fix->setModel (fixmodel);
        }
}

          The only problems I found:
          1.) The first row's height is much less than the rest of the rows.
          2.) The ID column is completely missing.
          Is this the model's issue or i cut the first column off somewhere?
          Thank you for all your help.

          1 Reply Last reply
          0
          • VRoninV Offline
            VRoninV Offline
            VRonin
            wrote on last edited by VRonin
            #13

            fixmodel->setData (fixmodel->index(row1,0),query_fix.value (0).toString ());

            don't call toString, setdata wants a QVariant, no need to convert anything

            The problems you mentioned look a lot like view issues rather than model issues? are you using a custom view or delegate?

            this

            monthf = query_fix.value (4).toString ();
            dayf = query_fix.value (5).toString ();
            yearf = query_fix.value (6).toString ();
            date = monthf + "/" + dayf + "/" + yearf;
fixmodel->setData (fixmodel->index(row1,7),date);

            is bad on so many levels.

            use

            fixmodel->setData (fixmodel->index(row1,7),QDate(query_fix.value (6).toInt(),query_fix.value (4).toInt(),query_fix.value (5).toInt());

            "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

            G 2 Replies Last reply
            0
            • VRoninV VRonin

              fixmodel->setData (fixmodel->index(row1,0),query_fix.value (0).toString ());

              don't call toString, setdata wants a QVariant, no need to convert anything

              The problems you mentioned look a lot like view issues rather than model issues? are you using a custom view or delegate?

              this

              monthf = query_fix.value (4).toString ();
            dayf = query_fix.value (5).toString ();
            yearf = query_fix.value (6).toString ();
            date = monthf + "/" + dayf + "/" + yearf;
fixmodel->setData (fixmodel->index(row1,7),date);

              is bad on so many levels.

              use

              fixmodel->setData (fixmodel->index(row1,7),QDate(query_fix.value (6).toInt(),query_fix.value (4).toInt(),query_fix.value (5).toInt());
              G Offline
              G Offline
              gabor53
              wrote on last edited by
              #14

              @VRonin said in QStandardItemModel doesn't display data:

              fixmodel->setData (fixmodel->index(row1,7),QDate(query_fix.value (6).toInt(),query_fix.value (4).toInt(),query_fix.value (5).toInt());

              I did the changes you recommended. The change is that in the Name column in the first row I have the ID. If I click on anywhere on the table, the ID from the first row disappears, replaced by the Name and the ID columns is still completely missing.

              1 Reply Last reply
              0
              • VRoninV VRonin

                fixmodel->setData (fixmodel->index(row1,0),query_fix.value (0).toString ());

                don't call toString, setdata wants a QVariant, no need to convert anything

                The problems you mentioned look a lot like view issues rather than model issues? are you using a custom view or delegate?

                this

                monthf = query_fix.value (4).toString ();
            dayf = query_fix.value (5).toString ();
            yearf = query_fix.value (6).toString ();
            date = monthf + "/" + dayf + "/" + yearf;
fixmodel->setData (fixmodel->index(row1,7),date);

                is bad on so many levels.

                use

                fixmodel->setData (fixmodel->index(row1,7),QDate(query_fix.value (6).toInt(),query_fix.value (4).toInt(),query_fix.value (5).toInt());
                G Offline
                G Offline
                gabor53
                wrote on last edited by
                #15

                @VRonin
                As it looks It displays the database from column 2.

                1 Reply Last reply
                0
                • VRoninV Offline
                  VRoninV Offline
                  VRonin
                  wrote on last edited by VRonin
                  #16

                  do you have any events linked to selection or click?

                  "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

                  G 2 Replies Last reply
                  0
                  • VRoninV VRonin

                    do you have any events linked to selection or click?

                    G Offline
                    G Offline
                    gabor53
                    wrote on last edited by
                    #17

                    @VRonin

                    No. Or at least not yet.

                    1 Reply Last reply
                    0
                    • VRoninV VRonin

                      do you have any events linked to selection or click?

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

                      @VRonin
                      The following code displays the ID column:

                      void FixDb::correctFriend()
{
    qDebug() << "Entered correctFriend!";

    QSqlQuery query_fix  ("SELECT ID 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 ();
        }

    while(query_fix.next ())
        {
            QString tempID = query_fix.value (0).toString ();
            qDebug() << "TempID: " << tempID;
        }

    QStandardItemModel *fixmodel = new QStandardItemModel(this);
    ui->tableView_fix->setModel (fixmodel);

    const QSqlRecord qR = query_fix.record ();
    qDebug() << "The number of records: " << qR;
    fixmodel->insertColumns (0,qR.count ());

    for(int row1 = 0; query_fix.next (); row1++)
        {
            fixmodel->insertRow (row1);
        }

    ui->tableView_fix->horizontalHeader ()->setStyleSheet ("QHeaderView{font: 14pt Arial; color: blue; font-weight: bold;text-decoration: underline;}");
    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"));

    ui->tableView_fix->setColumnWidth (0,100);
}

                      but when I add

                       fixmodel->setData (fixmodel->index(row1,0),query_fix.value (0));

                      after insertRow the column header disappears and the tableview is empty.

                      1 Reply Last reply
                      0
                      • VRoninV Offline
                        VRoninV Offline
                        VRonin
                        wrote on last edited by VRonin
                        #19

                        I have a strong suspect the problem lies in the view, could you try the code below and see if the column is displayed correctly?

                        void FixDb::correctFriend()
{
    qDebug() << "Entered correctFriend!";

    QSqlQuery query_fix  ("SELECT ID 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 ();
        }

    while(query_fix.next ())
        {
            QString tempID = query_fix.value (0).toString ();
            qDebug() << "TempID: " << tempID;
        }

    QStandardItemModel *fixmodel = new QStandardItemModel(this);
QTableView* tempView=new QTableView;
tempView->setAttribute( Qt::WA_DeleteOnClose ); // To prevent memory leak
    tempView->setModel (fixmodel);

    const QSqlRecord qR = query_fix.record ();
    qDebug() << "The number of records: " << qR;
    fixmodel->insertColumns (0,qR.count ());

    for(int row1 = 0; query_fix.next (); row1++)
        {
            fixmodel->insertRow (row1);
fixmodel->setData (fixmodel->index(row1,0),query_fix.value (0));
        }

   

    fixmodel->setHeaderData (0,Qt::Horizontal, QObject::tr("ID"));

    tempView->show();
}

                        "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

                        G 2 Replies Last reply
                        3
                        • VRoninV VRonin

                          I have a strong suspect the problem lies in the view, could you try the code below and see if the column is displayed correctly?

                          void FixDb::correctFriend()
{
    qDebug() << "Entered correctFriend!";

    QSqlQuery query_fix  ("SELECT ID 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 ();
        }

    while(query_fix.next ())
        {
            QString tempID = query_fix.value (0).toString ();
            qDebug() << "TempID: " << tempID;
        }

    QStandardItemModel *fixmodel = new QStandardItemModel(this);
QTableView* tempView=new QTableView;
tempView->setAttribute( Qt::WA_DeleteOnClose ); // To prevent memory leak
    tempView->setModel (fixmodel);

    const QSqlRecord qR = query_fix.record ();
    qDebug() << "The number of records: " << qR;
    fixmodel->insertColumns (0,qR.count ());

    for(int row1 = 0; query_fix.next (); row1++)
        {
            fixmodel->insertRow (row1);
fixmodel->setData (fixmodel->index(row1,0),query_fix.value (0));
        }

   

    fixmodel->setHeaderData (0,Qt::Horizontal, QObject::tr("ID"));

    tempView->show();
}
                          G Offline
                          G Offline
                          gabor53
                          wrote on last edited by
                          #20

                          @VRonin
                          It displays only the original tableview from the ui. I can't see tempView .

                          1 Reply Last reply
                          0
                          • VRoninV VRonin

                            I have a strong suspect the problem lies in the view, could you try the code below and see if the column is displayed correctly?

                            void FixDb::correctFriend()
{
    qDebug() << "Entered correctFriend!";

    QSqlQuery query_fix  ("SELECT ID 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 ();
        }

    while(query_fix.next ())
        {
            QString tempID = query_fix.value (0).toString ();
            qDebug() << "TempID: " << tempID;
        }

    QStandardItemModel *fixmodel = new QStandardItemModel(this);
QTableView* tempView=new QTableView;
tempView->setAttribute( Qt::WA_DeleteOnClose ); // To prevent memory leak
    tempView->setModel (fixmodel);

    const QSqlRecord qR = query_fix.record ();
    qDebug() << "The number of records: " << qR;
    fixmodel->insertColumns (0,qR.count ());

    for(int row1 = 0; query_fix.next (); row1++)
        {
            fixmodel->insertRow (row1);
fixmodel->setData (fixmodel->index(row1,0),query_fix.value (0));
        }

   

    fixmodel->setHeaderData (0,Qt::Horizontal, QObject::tr("ID"));

    tempView->show();
}
                            G Offline
                            G Offline
                            gabor53
                            wrote on last edited by
                            #21

                            @VRonin
                            I figured it out, but the new table shows only the header row with the title ID.

                            1 Reply Last reply
                            0
                            • VRoninV Offline
                              VRoninV Offline
                              VRonin
                              wrote on last edited by
                              #22

                              could you qDebug() << "Rows: " << fixmodel->rowCount() << " Columns: " << fixmodel->columnCount() just before tempView->show();?

                              "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

                              G 1 Reply Last reply
                              1
                              • VRoninV VRonin

                                could you qDebug() << "Rows: " << fixmodel->rowCount() << " Columns: " << fixmodel->columnCount() just before tempView->show();?

                                G Offline
                                G Offline
                                gabor53
                                wrote on last edited by
                                #23

                                @VRonin
                                I redid the whole class and it works now. I think there was something wrong with QTableView in Editor. Thank you for your help.

                                1 Reply Last reply
                                1

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