"QSortFilterProxyModel::lessThan" method doesn't work!

Hello,

I implement this virtual function from QSortFilterProxyModel so as to sort a table of datas.
My proxy is between a QAbstractTableModel and a QTableView. My datas are strings.

Here is the code :

Code:

---

bool DSSortFilterProxy::lessThan(const QModelIndex &left,
                                          const QModelIndex &right) const
    {
        QVariant leftData = sourceModel()->data(left);
        QVariant rightData = sourceModel()->data(right);
        return QString::localeAwareCompare(leftData.toString(), rightData.toString()) < 0;
    }

---

The problem is during the runtime, the function is never called. (i tried to put a message pop-up inside...).

How is this function called?
Should it be called when the header of a column is clicked in the TableView?

Thank you very much for your help.
Xelag

Are you using Qt 4.1 or 4.2? If latter, you may use QTableView::setSortingEnabled() to disable row/column selection from headers and to enable sorting instead. As far as I remember, in Qt 4.1 you had to do the same by hand.

From qtableview.cpp (Qt 4.2):

Code:

---

void QTableView::setSortingEnabled(bool enable)
{
    Q_D(QTableView);
    d->sortingEnabled = enable;
    horizontalHeader()->setSortIndicatorShown(enable);
    if (enable) {
        disconnect(horizontalHeader(), SIGNAL(sectionPressed(int)),
                   this, SLOT(selectColumn(int)));
        connect(horizontalHeader(), SIGNAL(sectionClicked(int)),
                this, SLOT(sortByColumn(int)));
        sortByColumn(horizontalHeader()->sortIndicatorSection());
    } else {
        connect(horizontalHeader(), SIGNAL(sectionPressed(int)),
                this, SLOT(selectColumn(int)));
        disconnect(horizontalHeader(), SIGNAL(sectionClicked(int)),
                   this, SLOT(sortByColumn(int)));
    }
}

---

Maybe you've already done this, but the header's sectionClicked( int ) signal needs to be connected to the TableView's sortByColumn( int ) slot... in 4.1 at least - not sure about 4.2.

I use 4.1 Qt version.

Quote:

---

[...]in Qt 4.1 you had to do the same by hand.

---

How can i do that?

But i don't understand yet why the function lessThan is not called...

Quote:

---

Originally Posted by xelag

I use 4.1 Qt version.

How can i do that?

---

See my previous post, I added the piece of code from Qt 4.2.

Quote:

---

But i don't understand yet why the function lessThan is not called...

---

QTableView is not sorting by default. Clicking on headers selects the whole row/column.

Another thing is to ensure you've called setClickable( true ) on the header as well.

Thank you very much! it works!

Code in the main programm :

Code:

---

QHeaderView *tmpHeaderView = tableView->horizontalHeader();
    tmpHeaderView->setClickable(true);
 
    tableView->setSortingEnabled(true);

---

Code in the class inherited form QTableView :

Code:

---

void DSTableView::setSortingEnabled(bool _enable)
{
 
 
     horizontalHeader()->setSortIndicatorShown(_enable);
 
     if (_enable)
     {
         disconnect(horizontalHeader(), SIGNAL(sectionPressed(int)),
                    this, SLOT(selectColumn(int)));
 
         connect(horizontalHeader(), SIGNAL(sectionClicked(int)),
                    this, SLOT(sortByColumn(int)));
 
         sortByColumn(horizontalHeader()->sortIndicatorSection());
     }
     else
     {
 
         connect(horizontalHeader(), SIGNAL(sectionPressed(int)),
                    this, SLOT(selectColumn(int)));
 
         disconnect(horizontalHeader(), SIGNAL(sectionClicked(int)),
                    this, SLOT(sortByColumn(int)));
     }
 
}

---

Thank you very much!
Xelag