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emredog
16th October 2009, 16:58
Hi,

i'm working on a windows application, where in a dialog i query some data from Postgres, and manually show the output in a table widget.


m_ui->tableWidget->setRowCount(joinedData.count());
for(int i=0; i<joinedData.count(); i++) //for each row
{
m_ui->tableWidget->setItem(i, 0, new QTableWidgetItem(joinedData[i].bobin.referenceNumber));
m_ui->tableWidget->setItem(i, 1, new QTableWidgetItem(QString::number(joinedData[i].bobin.width)));
m_ui->tableWidget->setItem(i, 2, new QTableWidgetItem(QString::number(joinedData[i].tolerance.getHole())));
m_ui->tableWidget->setItem(i, 3, new QTableWidgetItem(QString::number(joinedData[i].tolerance.getLessThanZeroFive())));
m_ui->tableWidget->setItem(i, 4, new QTableWidgetItem(QString::number(joinedData[i].tolerance.getZeroFive_to_zeroSeven())));
m_ui->tableWidget->setItem(i, 5, new QTableWidgetItem(QString::number(joinedData[i].tolerance.getZeroFive_to_zeroSeven_repetitive())) );
m_ui->tableWidget->setItem(i, 6, new QTableWidgetItem(QString::number(joinedData[i].tolerance.getZeroSeven_to_Three())));
m_ui->tableWidget->setItem(i, 7, new QTableWidgetItem(QString::number(joinedData[i].tolerance.getThree_to_five())));
m_ui->tableWidget->setItem(i, 8, new QTableWidgetItem(QString::number(joinedData[i].tolerance.getMoreThanFive())));
}


Also, based on row and column information, i paint some of these tablewidgetitems to some colors, but i don't think it's relevant.

I reimplemented the QDialog's contextMenuEvent, to obtain the right clicked tableWidgetItem's row and column coordinates:

(BobinFlanView is custom class derived from QDialog)

void BobinFlanView::contextMenuEvent(QContextMenuEvent *event)
{
QMenu menu(m_ui->tableWidget);
//standard actions
menu.addAction(this->markInactiveAction);
menu.addAction(this->markActiveAction);
menu.addSeparator();
menu.addAction(this->exportAction);
menu.addAction(this->exportAllAction);

//obtain the rightClickedItem
QTableWidgetItem* clickedItem = m_ui->tableWidget->itemAt(m_ui->tableWidget->mapFromGlobal(event->globalPos()));



// if it's a colored one, add some more actions
if (clickedItem && clickedItem->column()>1 && clickedItem->row()>0)
{
//this is a property, i'm keeping this for a later use
this->lastRightClickedItem = clickedItem;
//debug purpose:
QMessageBox::information(this, "", QString("clickedItem = %1, %2").arg(clickedItem->row()).arg(clickedItem->column()));
QMessageBox::information(this, "", QString("globalClick = %1, %2\ntransformedPos = %3, %4").arg(event->globalX()).arg(event->globalY())
.arg(m_ui->tableWidget->mapFromGlobal(event->globalPos()).x()).arg(m_ui->tableWidget->mapFromGlobal(event->globalPos()).y()));

menu.addSeparator();

menu.addAction(this->changeSelectedToleranceToUygun);
menu.addAction(this->changeSelectedToleranceToUyar);
menu.addAction(this->changeSelectedToleranceToDurdurUyar);

//... some other irrevelant 'enable/disable' activities

menu.exec(event->globalPos());
}



The problem is, when i right click on the same item i get the same global coordinates, but randomly different row-column information. For instance, the global pos is exactly 600,230 but row-column pair is randomly (5,3) and (4,3). I mean, what?!

Also, when i click to an item from the last to rows (later than 13, i guess) will never go into condition "if (clickedItem && clickedItem->column()>1 && clickedItem->row()>0)", i think it's mainly because 'clickedItem' is null.

I'll be more than glad to share any more information, or even the full cpp-h-ui trio in order to get help.

Thanks a lot.

Lykurg
16th October 2009, 17:19
QTableWidgetItem* clickedItem = m_ui->tableWidget->itemAt(m_ui->tableWidget->mapFromGlobal(event->globalPos()));

You probably have to add the offset caused by the scrolling of your table widget.

emredog
19th October 2009, 08:50
thanks.

some guy from stackoverflow proposed a better solution, i would like to share it here:


The problem is that you are trying to map the global position to the table widget position, without considering the scrollable area. To map the global position into something you can pass to itemAt, use
tableWidget->viewport()->mapFromGlobal.