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
Change-Id: I191c3878819b99897083039fba0ab43908da5429
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
(cherry picked from commit f11e5435c776deddf27f7759180c1d41f64b8cce)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

2 files changed, 37 insertions, 1 deletions

diff --git a/src/widgets/itemviews/qabstractitemview.cpp b/src/widgets/itemviews/qabstractitemview.cpp
index 7a7b5c4753..d7d9a40b3f 100644
--- a/src/widgets/itemviews/qabstractitemview.cpp
+++ b/src/widgets/itemviews/qabstractitemview.cpp
@@ -4091,8 +4091,12 @@ 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();
diff --git a/tests/auto/widgets/itemviews/qabstractitemview/tst_qabstractitemview.cpp b/tests/auto/widgets/itemviews/qabstractitemview/tst_qabstractitemview.cpp
index 01e50380f8..31d98386f5 100644
--- a/tests/auto/widgets/itemviews/qabstractitemview/tst_qabstractitemview.cpp
+++ b/tests/auto/widgets/itemviews/qabstractitemview/tst_qabstractitemview.cpp
@@ -140,6 +140,7 @@ private slots:
     void selectionCommand();
     void mouseSelection_data();
     void mouseSelection();
+    void keepSingleSelectionOnEmptyAreaClick();
     void scrollerSmoothScroll();
     void inputMethodOpensEditor_data();
     void inputMethodOpensEditor();
@@ -3077,6 +3078,37 @@ void tst_QAbstractItemView::mouseSelection()
 }
 
 /*!
+    Make sure that when clicking on empty space in the view, we don't
+    unselect the current row.
+    QTBUG-105870
+*/
+void tst_QAbstractItemView::keepSingleSelectionOnEmptyAreaClick()
+{
+    QListWidget view;
+    view.setSelectionMode(QAbstractItemView::SingleSelection);
+    QListWidgetItem *lastItem;
+    for (int i = 0; i < 5; i++)
+        lastItem = new QListWidgetItem("item " + QString::number(i), &view);
+
+    // Make widget large enough so that there is empty area below the last item
+    view.setFixedSize(300, 500);
+    view.show();
+    QVERIFY(QTest::qWaitForWindowActive(&view));
+
+    // Select third row
+    view.setCurrentRow(2);
+
+    // Click below the last row
+    QPoint targetPoint = view.visualItemRect(lastItem).bottomLeft();
+    targetPoint += QPoint(10, 10);
+
+    QTest::mouseClick(view.viewport(), Qt::MouseButton::LeftButton, Qt::NoModifier, targetPoint);
+
+    QCOMPARE(view.currentRow(), 2);
+    QVERIFY(view.currentItem()->isSelected());
+}
+
+/*!
     Verify that scrolling an autoScroll enabled itemview with a QScroller
     produces a continuous, smooth scroll without any jumping around due to
     the currentItem negotiation between QAbstractItemView and QScroller.