QAItemView: in MultiSelection, press deselects only if no drag can start

In MultiSelection mode, items are by default toggled on press, which
follows the example of standard Windows controls. However, when dragging
is enabled, then the press might be the beginning of a drag'n'drop
operation, and deselecting the item on press breaks the selection and user
experience.

Don't toggle the selection for presses on an already selected item that
might get dragged; instead, wait for the release event.

Extend the test case slightly to cover the special case. Dragging a
selection in a drag-enabled and MultiSelection item view wasn't possible
before either.

Fixes: QTBUG-59888
Change-Id: Ibd3e95a71ea63dd1e9bc3c8a723eafa9a1c21afa
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
Reviewed-by: David Skoland <david.skoland@qt.io>

1 files changed, 19 insertions, 10 deletions

diff --git a/tests/auto/widgets/itemviews/qabstractitemview/tst_qabstractitemview.cpp b/tests/auto/widgets/itemviews/qabstractitemview/tst_qabstractitemview.cpp
index e7637f8013..69fac4bd96 100644
--- a/tests/auto/widgets/itemviews/qabstractitemview/tst_qabstractitemview.cpp
+++ b/tests/auto/widgets/itemviews/qabstractitemview/tst_qabstractitemview.cpp
@@ -2790,9 +2790,14 @@ void tst_QAbstractItemView::mouseSelection_data()
         << QList{SelectionEvent(SelectionEvent::Press, 1),
                  SelectionEvent(SelectionEvent::Press, 1)}
         << QList<int>{};
-    QTest::addRow("Multi:Click") << QAbstractItemView::MultiSelection << false
-        << QList{SelectionEvent(SelectionEvent::Click, 2)}
-        << QList{2};
+    QTest::addRow("Multi:Press twice with drag enabled") << QAbstractItemView::MultiSelection << true
+        << QList{SelectionEvent(SelectionEvent::Click, 1),
+                 SelectionEvent(SelectionEvent::Press, 1)}
+        << QList{1};
+    QTest::addRow("Multi:Press and click with drag enabled") << QAbstractItemView::MultiSelection << true
+        << QList{SelectionEvent(SelectionEvent::Press, 1),
+                 SelectionEvent(SelectionEvent::Click, 1)}
+        << QList<int>{};
     QTest::addRow("Multi:Press,Press") << QAbstractItemView::MultiSelection << false
         << QList{SelectionEvent(SelectionEvent::Press, 2),
                  SelectionEvent(SelectionEvent::Press, 3)}
@@ -2828,11 +2833,15 @@ void tst_QAbstractItemView::mouseSelection_data()
         << QList{3, 4};
     // Multi: Press-dragging a selection should not deselect #QTBUG-59888
     QTest::addRow("Multi:Press-Drag selection") << QAbstractItemView::MultiSelection << true
-        << QList{SelectionEvent(SelectionEvent::Press, 2),
-                 SelectionEvent(SelectionEvent::Move, 5),
-                 SelectionEvent(SelectionEvent::Release),
+        // with drag'n'drop enabled, we cannot drag a selection
+        << QList{SelectionEvent(SelectionEvent::Click, 2),
+                 SelectionEvent(SelectionEvent::Click, 3),
+                 SelectionEvent(SelectionEvent::Click, 4),
+                 SelectionEvent(SelectionEvent::Click, 5),
                  SelectionEvent(SelectionEvent::Press, 3),
-                 SelectionEvent(SelectionEvent::Move, 5)}
+                 // two moves needed because of distance and state logic in QAbstractItemView
+                 SelectionEvent(SelectionEvent::Move, 5),
+                 SelectionEvent(SelectionEvent::Move, 6)}
         << QList{2, 3, 4, 5};
 
     // Extended selection: Press selects a single item
@@ -2962,12 +2971,12 @@ void tst_QAbstractItemView::mouseSelection()
     }
 
     QList<int> actualSelected;
-    const auto selectedIndexes = dragEnabled ? dragRecorder->draggedIndexes
-                                             : view->selectionModel()->selectedIndexes();
+    const auto selectedIndexes = dragRecorder->dragStarted
+                               ? dragRecorder->draggedIndexes
+                               : view->selectionModel()->selectedIndexes();
     for (auto index : selectedIndexes)
         actualSelected << index.row();
 
-    QEXPECT_FAIL("Multi:Press-Drag selection", "QTBUG-59889", Continue);
     QCOMPARE(actualSelected, selectedRows);
 }