QAbstractScrollArea: Wheel over a scrollarea that has only one horizontal scrollbar

If the vertical scrollbar is hidden, scroll using the other scrollbar.

Reviewed-by: Thierry
Task-number: QTBUG-1760

2 files changed, 7 insertions, 6 deletions

diff --git a/src/gui/widgets/qabstractscrollarea.cpp b/src/gui/widgets/qabstractscrollarea.cpp
index 48099ef..c186645 100644
--- a/src/gui/widgets/qabstractscrollarea.cpp
+++ b/src/gui/widgets/qabstractscrollarea.cpp
@@ -1130,10 +1130,13 @@ void QAbstractScrollArea::mouseMoveEvent(QMouseEvent *e)
 void QAbstractScrollArea::wheelEvent(QWheelEvent *e)
 {
     Q_D(QAbstractScrollArea);
-    if (static_cast<QWheelEvent*>(e)->orientation() == Qt::Horizontal)
-        QApplication::sendEvent(d->hbar, e);
-    else
-        QApplication::sendEvent(d->vbar, e);
+    QScrollBar *const bars[2] = { d->hbar, d->vbar };
+    int idx = (e->orientation() == Qt::Vertical) ? 1 : 0;
+    int other = (idx + 1) % 2;
+    if (!bars[idx]->isVisible() && bars[other]->isVisible())
+        idx = other;   // If the scrollbar of the event orientation is hidden, fallback to the other.
+
+    QApplication::sendEvent(bars[idx], e);
 }
 #endif
 
diff --git a/src/gui/widgets/qabstractslider.cpp b/src/gui/widgets/qabstractslider.cpp
index fec9fab..e0db9c2 100644
--- a/src/gui/widgets/qabstractslider.cpp
+++ b/src/gui/widgets/qabstractslider.cpp
@@ -690,8 +690,6 @@ void QAbstractSlider::wheelEvent(QWheelEvent * e)
 {
     Q_D(QAbstractSlider);
     e->ignore();
-    if (e->orientation() != d->orientation && !rect().contains(e->pos()))
-        return;
 
     int stepsToScroll = 0;
     qreal offset = qreal(e->delta()) / 120;