1 files changed, 81 insertions, 57 deletions

diff --git a/src/templates/qquickslider.cpp b/src/templates/qquickslider.cpp
index fac8fb50..395725eb 100644
--- a/src/templates/qquickslider.cpp
+++ b/src/templates/qquickslider.cpp
@@ -47,7 +47,7 @@ QT_BEGIN_NAMESPACE
     \instantiates QQuickSlider
     \inqmlmodule Qt.labs.controls
     \ingroup qtlabscontrols-input
-    \brief A slider control.
+    \brief Selects a value by sliding a handle along a track.
 
     \image qtlabscontrols-slider.gif
 
@@ -80,7 +80,7 @@ class QQuickSliderPrivate : public QQuickControlPrivate
 public:
     QQuickSliderPrivate() : from(0), to(1), value(0), position(0), stepSize(0), pressed(false),
         orientation(Qt::Horizontal), snapMode(QQuickSlider::NoSnap),
-        handle(Q_NULLPTR), track(Q_NULLPTR)
+        handle(nullptr), track(nullptr)
     {
     }
 
@@ -147,11 +147,12 @@ void QQuickSliderPrivate::setPosition(qreal pos)
 {
     Q_Q(QQuickSlider);
     pos = qBound<qreal>(0.0, pos, 1.0);
-    if (!qFuzzyCompare(position, pos)) {
-        position = pos;
-        emit q->positionChanged();
-        emit q->visualPositionChanged();
-    }
+    if (qFuzzyCompare(position, pos))
+        return;
+
+    position = pos;
+    emit q->positionChanged();
+    emit q->visualPositionChanged();
 }
 
 void QQuickSliderPrivate::updatePosition()
@@ -185,13 +186,14 @@ qreal QQuickSlider::from() const
 void QQuickSlider::setFrom(qreal from)
 {
     Q_D(QQuickSlider);
-    if (!qFuzzyCompare(d->from, from)) {
-        d->from = from;
-        emit fromChanged();
-        if (isComponentComplete()) {
-            setValue(d->value);
-            d->updatePosition();
-        }
+    if (qFuzzyCompare(d->from, from))
+        return;
+
+    d->from = from;
+    emit fromChanged();
+    if (isComponentComplete()) {
+        setValue(d->value);
+        d->updatePosition();
     }
 }
 
@@ -211,13 +213,14 @@ qreal QQuickSlider::to() const
 void QQuickSlider::setTo(qreal to)
 {
     Q_D(QQuickSlider);
-    if (!qFuzzyCompare(d->to, to)) {
-        d->to = to;
-        emit toChanged();
-        if (isComponentComplete()) {
-            setValue(d->value);
-            d->updatePosition();
-        }
+    if (qFuzzyCompare(d->to, to))
+        return;
+
+    d->to = to;
+    emit toChanged();
+    if (isComponentComplete()) {
+        setValue(d->value);
+        d->updatePosition();
     }
 }
 
@@ -244,11 +247,12 @@ void QQuickSlider::setValue(qreal value)
     if (isComponentComplete())
         value = d->from > d->to ? qBound(d->to, value, d->from) : qBound(d->from, value, d->to);
 
-    if (!qFuzzyCompare(d->value, value)) {
-        d->value = value;
-        d->updatePosition();
-        emit valueChanged();
-    }
+    if (qFuzzyCompare(d->value, value))
+        return;
+
+    d->value = value;
+    d->updatePosition();
+    emit valueChanged();
 }
 
 /*!
@@ -307,10 +311,11 @@ qreal QQuickSlider::stepSize() const
 void QQuickSlider::setStepSize(qreal step)
 {
     Q_D(QQuickSlider);
-    if (!qFuzzyCompare(d->stepSize, step)) {
-        d->stepSize = step;
-        emit stepSizeChanged();
-    }
+    if (qFuzzyCompare(d->stepSize, step))
+        return;
+
+    d->stepSize = step;
+    emit stepSizeChanged();
 }
 
 /*!
@@ -334,10 +339,11 @@ QQuickSlider::SnapMode QQuickSlider::snapMode() const
 void QQuickSlider::setSnapMode(SnapMode mode)
 {
     Q_D(QQuickSlider);
-    if (d->snapMode != mode) {
-        d->snapMode = mode;
-        emit snapModeChanged();
-    }
+    if (d->snapMode == mode)
+        return;
+
+    d->snapMode = mode;
+    emit snapModeChanged();
 }
 
 /*!
@@ -354,11 +360,12 @@ bool QQuickSlider::isPressed() const
 void QQuickSlider::setPressed(bool pressed)
 {
     Q_D(QQuickSlider);
-    if (d->pressed != pressed) {
-        d->pressed = pressed;
-        setAccessibleProperty("pressed", pressed);
-        emit pressedChanged();
-    }
+    if (d->pressed == pressed)
+        return;
+
+    d->pressed = pressed;
+    setAccessibleProperty("pressed", pressed);
+    emit pressedChanged();
 }
 
 /*!
@@ -379,10 +386,11 @@ Qt::Orientation QQuickSlider::orientation() const
 void QQuickSlider::setOrientation(Qt::Orientation orientation)
 {
     Q_D(QQuickSlider);
-    if (d->orientation != orientation) {
-        d->orientation = orientation;
-        emit orientationChanged();
-    }
+    if (d->orientation == orientation)
+        return;
+
+    d->orientation = orientation;
+    emit orientationChanged();
 }
 
 /*!
@@ -401,13 +409,14 @@ QQuickItem *QQuickSlider::handle() const
 void QQuickSlider::setHandle(QQuickItem *handle)
 {
     Q_D(QQuickSlider);
-    if (d->handle != handle) {
-        delete d->handle;
-        d->handle = handle;
-        if (handle && !handle->parentItem())
-            handle->setParentItem(this);
-        emit handleChanged();
-    }
+    if (d->handle == handle)
+        return;
+
+    delete d->handle;
+    d->handle = handle;
+    if (handle && !handle->parentItem())
+        handle->setParentItem(this);
+    emit handleChanged();
 }
 
 /*!
@@ -426,13 +435,14 @@ QQuickItem *QQuickSlider::track() const
 void QQuickSlider::setTrack(QQuickItem *track)
 {
     Q_D(QQuickSlider);
-    if (d->track != track) {
-        delete d->track;
-        d->track = track;
-        if (track && !track->parentItem())
-            track->setParentItem(this);
-        emit trackChanged();
-    }
+    if (d->track == track)
+        return;
+
+    delete d->track;
+    d->track = track;
+    if (track && !track->parentItem())
+        track->setParentItem(this);
+    emit trackChanged();
 }
 
 /*!
@@ -555,6 +565,20 @@ void QQuickSlider::mouseUngrabEvent()
     setPressed(false);
 }
 
+void QQuickSlider::wheelEvent(QWheelEvent *event)
+{
+    Q_D(QQuickSlider);
+    QQuickControl::wheelEvent(event);
+    if (d->wheelEnabled) {
+        const qreal oldValue = d->value;
+        const QPointF angle = event->angleDelta();
+        const qreal delta = (qFuzzyIsNull(angle.y()) ? angle.x() : angle.y()) / QWheelEvent::DefaultDeltasPerStep;
+        const qreal step = qFuzzyIsNull(d->stepSize) ? 0.1 : d->stepSize;
+        setValue(oldValue + step * delta);
+        event->setAccepted(!qFuzzyCompare(d->value, oldValue));
+    }
+}
+
 void QQuickSlider::mirrorChange()
 {
     QQuickControl::mirrorChange();