QAbstractItemView: Don't unselect on click on empty area in SingleSelect

dfb4697e4a4828acd47292a89207b3975ec6766e made a change to selection
behavior that resulted in a regression where clicking on an item view
but not on an item would cause the current item to get unselected.
Changes the behavior to not update in this case.

Added a new test that specifially checks for this scenario and ensures
that the current item is still selected, even after the user clicks on
empty area.

Fixes: QTBUG-105870
Pick-to: 6.2 6.4 6.5
Change-Id: I191c3878819b99897083039fba0ab43908da5429
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

1 files changed, 5 insertions, 1 deletions

diff --git a/src/widgets/itemviews/qabstractitemview.cpp b/src/widgets/itemviews/qabstractitemview.cpp
index 1619635dbf..179e542ccc 100644
--- a/src/widgets/itemviews/qabstractitemview.cpp
+++ b/src/widgets/itemviews/qabstractitemview.cpp
@@ -4093,8 +4093,12 @@ QItemSelectionModel::SelectionFlags QAbstractItemView::selectionCommand(const QM
                     if (d->pressedAlreadySelected)
                         return QItemSelectionModel::NoUpdate;
                     break;
-                case QEvent::KeyPress:
                 case QEvent::MouseButtonRelease:
+                    // clicking into area with no items does nothing
+                    if (!index.isValid())
+                        return QItemSelectionModel::NoUpdate;
+                    Q_FALLTHROUGH();
+                case QEvent::KeyPress:
                     // ctrl-release on selected item deselects
                     if ((keyModifiers & Qt::ControlModifier) && d->selectionModel->isSelected(index))
                         return QItemSelectionModel::Deselect | d->selectionBehaviorFlags();