QTreeView: Select One or None - close, but no cigar.

LiamMaru

So, I'm keen to make a QTreeView select a single index to pick an item, or select nothing by clicking empty space. I found this very helpful hint:

"http://stackoverflow.com/questions/2761284/is-it-possible-to-deselect-in-a-qtreeview-by-clicking-off-an-item
":http://stackoverflow.com/questions/2761284/is-it-possible-to-deselect-in-a-qtreeview-by-clicking-off-an-item

Which got me pretty far. My equivalent method in C++ is:

@
void DeselectableTreeView::mousePressEvent(QMouseEvent* event)
{
this->clearSelection();
QTreeView::mousePressEvent(event);

if(!this->selectedIndexes().count())
{
emit selection_cleared();
}
}
@

However, adding the if(!this->selectedIndexes().count()){...} line causes windows to trigger a breakpoint:

HEAP[LMGM.exe]: Invalid address specified to RtlValidateHeap( 00210000, 02798DE8 )

Now, keep in mind, this signal isn't connected to anything. the code is simply there. If I remove the code, the application runs as expected. Any idea's as to how to solve this, what I've done wrong, or a more desirable way to implement the desired behavior?

LiamMaru

A slight addendum: I need to know when 'nothing' is selected, hence the signal. As a work around, I'm picking up on the escape key which is nice (and will stay) but I'd really like the ability to de-select by clicking empty space.

dangelog

I would change the logic into something like

@
QModelIndex index = indexAt(event->pos());
if (index.isValid()) {
selectionModel()->select(index, QItemSelectionModel::ClearAndSelect);
} else {
clearSelection();
}
@

By the way, you can connect a slot the QItemSelecitonModel::selectionChanged signal (the QISM on the view is available through selectionModel()).