Fix bug when highlight was not respected after currentIndex changed

QQuickListViewPrivate::fixup() seems to only do "fixup" if

  moveReason != QQuickListViewPrivate::SetIndex

By default, moveReason is set to Other. In the snippet given in
QTBUG-77418, this is why the highlight was respected when resizing the
ListView initially. However, after the currentIndex was changed,
moveReason was changed to SetIndex. When we then resized the ListView, it
still had the value SetIndex, and would fail to "fixup" properly.

Since the ListView preferredHighlightBegin is bound to width, we should
set moveReason to Other in the property setters that are related to
highlight. This is then consistent with how setCurrentIndex() does it (it
similarly sets d->moveReason = QQuickItemViewPrivate::SetIndex;)

Change-Id: I7edf77fc977e8c7e3fc656ff5bb22b4dd01afbe4
Task-number: QTBUG-77418
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

2 files changed, 38 insertions, 4 deletions

diff --git a/src/quick/items/qquickitemview.cpp b/src/quick/items/qquickitemview.cpp
index bbfbf6244c..b37fb69fae 100644
--- a/src/quick/items/qquickitemview.cpp
+++ b/src/quick/items/qquickitemview.cpp
@@ -599,6 +599,7 @@ void QQuickItemView::setHighlightRangeMode(HighlightRangeMode mode)
     d->haveHighlightRange = d->highlightRange != NoHighlightRange && d->highlightRangeStart <= d->highlightRangeEnd;
     if (isComponentComplete()) {
         d->updateViewport();
+        d->moveReason = QQuickItemViewPrivate::Other;
         d->fixupPosition();
     }
     emit highlightRangeModeChanged();
@@ -621,8 +622,10 @@ void QQuickItemView::setPreferredHighlightBegin(qreal start)
     d->haveHighlightRange = d->highlightRange != NoHighlightRange && d->highlightRangeStart <= d->highlightRangeEnd;
     if (isComponentComplete()) {
         d->updateViewport();
-        if (!isMoving() && !isFlicking())
+        if (!isMoving() && !isFlicking()) {
+            d->moveReason = QQuickItemViewPrivate::Other;
             d->fixupPosition();
+        }
     }
     emit preferredHighlightBeginChanged();
 }
@@ -636,8 +639,10 @@ void QQuickItemView::resetPreferredHighlightBegin()
     d->highlightRangeStart = 0;
     if (isComponentComplete()) {
         d->updateViewport();
-        if (!isMoving() && !isFlicking())
+        if (!isMoving() && !isFlicking()) {
+            d->moveReason = QQuickItemViewPrivate::Other;
             d->fixupPosition();
+        }
     }
     emit preferredHighlightBeginChanged();
 }
@@ -658,8 +663,10 @@ void QQuickItemView::setPreferredHighlightEnd(qreal end)
     d->haveHighlightRange = d->highlightRange != NoHighlightRange && d->highlightRangeStart <= d->highlightRangeEnd;
     if (isComponentComplete()) {
         d->updateViewport();
-        if (!isMoving() && !isFlicking())
+        if (!isMoving() && !isFlicking()) {
+            d->moveReason = QQuickItemViewPrivate::Other;
             d->fixupPosition();
+        }
     }
     emit preferredHighlightEndChanged();
 }
@@ -673,8 +680,10 @@ void QQuickItemView::resetPreferredHighlightEnd()
     d->highlightRangeEnd = 0;
     if (isComponentComplete()) {
         d->updateViewport();
-        if (!isMoving() && !isFlicking())
+        if (!isMoving() && !isFlicking()) {
+            d->moveReason = QQuickItemViewPrivate::Other;
             d->fixupPosition();
+        }
     }
     emit preferredHighlightEndChanged();
 }
diff --git a/tests/auto/quick/qquicklistview/tst_qquicklistview.cpp b/tests/auto/quick/qquicklistview/tst_qquicklistview.cpp
index b896418de0..9419dae362 100644
--- a/tests/auto/quick/qquicklistview/tst_qquicklistview.cpp
+++ b/tests/auto/quick/qquicklistview/tst_qquicklistview.cpp
@@ -1943,6 +1943,31 @@ void tst_QQuickListView::enforceRange()
 
     QTRY_COMPARE(listview->currentIndex(), 6);
 
+    // Test for [QTBUG-77418] {
+        // explicit set current index
+        listview->setCurrentIndex(5);
+        QTRY_COMPARE(listview->contentY(), 0);
+
+        // then check if contentY changes if the highlight range is changed
+        listview->setPreferredHighlightBegin(80);
+        listview->setPreferredHighlightEnd(80);
+        QTRY_COMPARE(listview->contentY(), 20);
+
+        // verify that current index does not change with no highlight
+        listview->setHighlightRangeMode(QQuickListView::NoHighlightRange);
+        listview->setContentY(100);
+        QTRY_COMPARE(listview->currentIndex(), 5);
+
+        // explicit set current index, contentY should not change now
+        listview->setCurrentIndex(6);
+        QTRY_COMPARE(listview->contentY(), 100);
+        QTest::qWait(50);   // This was needed in order to reproduce a failure for the following test
+
+        // verify that contentY changes if we turn on highlight again
+        listview->setHighlightRangeMode(QQuickListView::StrictlyEnforceRange);
+        QTRY_COMPARE(listview->contentY(), 40);
+    // } Test for [QTBUG-77418]
+
     // change model
     QaimModel model2;
     for (int i = 0; i < 5; i++)