Fix PointerHandler constructors and destructors

- Constructors should take QQuickItem* not QObject* to be symmetric
  with the parentItem() accessor (and other code) which assumes its type
- Use header initialization everywhere possible
- Reorder variables to minimize padding (somewhat)
- Remove empty destructor bodies (the compiler can write them)
- Remove override and virtual from destructors in accordance with
  https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#Rh-override

Change-Id: I682a53a803d65e29136bfaec3a5b534e975ecf30
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>

21 files changed, 53 insertions, 114 deletions

diff --git a/src/quick/handlers/qquickdraghandler.cpp b/src/quick/handlers/qquickdraghandler.cpp
index 7c175b472b..d9f0e477d1 100644
--- a/src/quick/handlers/qquickdraghandler.cpp
+++ b/src/quick/handlers/qquickdraghandler.cpp
@@ -88,15 +88,11 @@ Q_LOGGING_CATEGORY(lcDragHandler, "qt.quick.handler.drag")
     \sa Drag, MouseArea
 */
 
-QQuickDragHandler::QQuickDragHandler(QObject *parent)
+QQuickDragHandler::QQuickDragHandler(QQuickItem *parent)
     : QQuickMultiPointHandler(parent, 1, 1)
 {
 }
 
-QQuickDragHandler::~QQuickDragHandler()
-{
-}
-
 bool QQuickDragHandler::targetContainsCentroid()
 {
     Q_ASSERT(parentItem() && target());
diff --git a/src/quick/handlers/qquickdraghandler_p.h b/src/quick/handlers/qquickdraghandler_p.h
index ea49d59902..25101a98c4 100644
--- a/src/quick/handlers/qquickdraghandler_p.h
+++ b/src/quick/handlers/qquickdraghandler_p.h
@@ -64,8 +64,7 @@ class Q_AUTOTEST_EXPORT QQuickDragHandler : public QQuickMultiPointHandler
     Q_PROPERTY(QVector2D translation READ translation NOTIFY translationChanged)
 
 public:
-    explicit QQuickDragHandler(QObject *parent = nullptr);
-    ~QQuickDragHandler();
+    explicit QQuickDragHandler(QQuickItem *parent = nullptr);
 
     void handlePointerEventImpl(QQuickPointerEvent *event) override;
 
diff --git a/src/quick/handlers/qquickhandlerpoint.cpp b/src/quick/handlers/qquickhandlerpoint.cpp
index be9bad7bea..f615829d97 100644
--- a/src/quick/handlers/qquickhandlerpoint.cpp
+++ b/src/quick/handlers/qquickhandlerpoint.cpp
@@ -72,9 +72,6 @@ Q_DECLARE_LOGGING_CATEGORY(DBG_TOUCH_TARGET)
 */
 
 QQuickHandlerPoint::QQuickHandlerPoint()
-    : m_id(0)
-    , m_rotation(0)
-    , m_pressure(0)
 {}
 
 void QQuickHandlerPoint::localize(QQuickItem *item)
diff --git a/src/quick/handlers/qquickhandlerpoint_p.h b/src/quick/handlers/qquickhandlerpoint_p.h
index 200d5bc825..44fd830af2 100644
--- a/src/quick/handlers/qquickhandlerpoint_p.h
+++ b/src/quick/handlers/qquickhandlerpoint_p.h
@@ -97,18 +97,18 @@ public:
     void reset(const QVector<QQuickHandlerPoint> &points);
 
 private:
-    int m_id;
+    int m_id = 0;
     QPointingDeviceUniqueId m_uniqueId;
-    Qt::MouseButtons m_pressedButtons;
-    Qt::KeyboardModifiers m_pressedModifiers;
+    Qt::MouseButtons m_pressedButtons = Qt::NoButton;
+    Qt::KeyboardModifiers m_pressedModifiers = Qt::NoModifier;
     QPointF m_position;
     QPointF m_scenePosition;
     QPointF m_pressPosition;
     QPointF m_scenePressPosition;
     QPointF m_sceneGrabPosition;
     QVector2D m_velocity;
-    qreal m_rotation;
-    qreal m_pressure;
+    qreal m_rotation = 0;
+    qreal m_pressure = 0;
     QSizeF m_ellipseDiameters;
     friend class QQuickMultiPointHandler;
     friend class QQuickSinglePointHandler;
diff --git a/src/quick/handlers/qquickhoverhandler.cpp b/src/quick/handlers/qquickhoverhandler.cpp
index 817c1348e6..ef6fb4eb7e 100644
--- a/src/quick/handlers/qquickhoverhandler.cpp
+++ b/src/quick/handlers/qquickhoverhandler.cpp
@@ -56,9 +56,8 @@ Q_LOGGING_CATEGORY(lcHoverHandler, "qt.quick.handler.hover")
     \sa MouseArea
 */
 
-QQuickHoverHandler::QQuickHoverHandler(QObject *parent)
+QQuickHoverHandler::QQuickHoverHandler(QQuickItem *parent)
     : QQuickSinglePointHandler(parent)
-    , m_hovered(false)
 {
     // Rule out the touchscreen for now (can be overridden in QML in case a hover-detecting touchscreen exists)
     setAcceptedDevices(static_cast<QQuickPointerDevice::DeviceType>(
diff --git a/src/quick/handlers/qquickhoverhandler_p.h b/src/quick/handlers/qquickhoverhandler_p.h
index 876d01761b..1ee2aeb7e6 100644
--- a/src/quick/handlers/qquickhoverhandler_p.h
+++ b/src/quick/handlers/qquickhoverhandler_p.h
@@ -64,7 +64,7 @@ class Q_AUTOTEST_EXPORT QQuickHoverHandler : public QQuickSinglePointHandler
     Q_PROPERTY(bool hovered READ isHovered NOTIFY hoveredChanged)
 
 public:
-    explicit QQuickHoverHandler(QObject *parent = 0);
+    explicit QQuickHoverHandler(QQuickItem *parent = nullptr);
     ~QQuickHoverHandler();
 
     bool isHovered() const { return m_hovered; }
@@ -81,7 +81,7 @@ private:
     void setHovered(bool hovered);
 
 private:
-    bool m_hovered;
+    bool m_hovered = false;
 };
 
 QT_END_NAMESPACE
diff --git a/src/quick/handlers/qquickmultipointhandler.cpp b/src/quick/handlers/qquickmultipointhandler.cpp
index 98321e134a..687bccdc4f 100644
--- a/src/quick/handlers/qquickmultipointhandler.cpp
+++ b/src/quick/handlers/qquickmultipointhandler.cpp
@@ -58,17 +58,13 @@ QT_BEGIN_NAMESPACE
     for any type of handler which requires and acts upon a specific number
     of multiple touchpoints.
 */
-QQuickMultiPointHandler::QQuickMultiPointHandler(QObject *parent, int minimumPointCount, int maximumPointCount)
+QQuickMultiPointHandler::QQuickMultiPointHandler(QQuickItem *parent, int minimumPointCount, int maximumPointCount)
     : QQuickPointerDeviceHandler(parent)
     , m_minimumPointCount(minimumPointCount)
     , m_maximumPointCount(maximumPointCount)
 {
 }
 
-QQuickMultiPointHandler::~QQuickMultiPointHandler()
-{
-}
-
 bool QQuickMultiPointHandler::wantsPointerEvent(QQuickPointerEvent *event)
 {
     if (!QQuickPointerDeviceHandler::wantsPointerEvent(event))
diff --git a/src/quick/handlers/qquickmultipointhandler_p.h b/src/quick/handlers/qquickmultipointhandler_p.h
index fbd9f378a3..199ea7cd10 100644
--- a/src/quick/handlers/qquickmultipointhandler_p.h
+++ b/src/quick/handlers/qquickmultipointhandler_p.h
@@ -66,8 +66,7 @@ class Q_AUTOTEST_EXPORT QQuickMultiPointHandler : public QQuickPointerDeviceHand
     Q_PROPERTY(QQuickHandlerPoint centroid READ centroid NOTIFY centroidChanged)
 
 public:
-    explicit QQuickMultiPointHandler(QObject *parent = nullptr, int minimumPointCount = 2, int maximumPointCount = -1);
-    ~QQuickMultiPointHandler();
+    explicit QQuickMultiPointHandler(QQuickItem *parent = nullptr, int minimumPointCount = 2, int maximumPointCount = -1);
 
     int minimumPointCount() const { return m_minimumPointCount; }
     void setMinimumPointCount(int c);
diff --git a/src/quick/handlers/qquickpinchhandler.cpp b/src/quick/handlers/qquickpinchhandler.cpp
index d6e1a183bb..75a2847aa0 100644
--- a/src/quick/handlers/qquickpinchhandler.cpp
+++ b/src/quick/handlers/qquickpinchhandler.cpp
@@ -85,27 +85,8 @@ Q_LOGGING_CATEGORY(lcPinchHandler, "qt.quick.handler.pinch")
     \sa PinchArea
 */
 
-QQuickPinchHandler::QQuickPinchHandler(QObject *parent)
+QQuickPinchHandler::QQuickPinchHandler(QQuickItem *parent)
     : QQuickMultiPointHandler(parent, 2)
-    , m_activeScale(1)
-    , m_accumulatedScale(1)
-    , m_activeRotation(0)
-    , m_activeTranslation(0,0)
-    , m_minimumScale(-qInf())
-    , m_maximumScale(qInf())
-    , m_minimumRotation(-qInf())
-    , m_maximumRotation(qInf())
-    , m_minimumX(-qInf())
-    , m_maximumX(qInf())
-    , m_minimumY(-qInf())
-    , m_maximumY(qInf())
-    , m_pinchOrigin(PinchCenter)
-    , m_startScale(1)
-    , m_startRotation(0)
-{
-}
-
-QQuickPinchHandler::~QQuickPinchHandler()
 {
 }
 
diff --git a/src/quick/handlers/qquickpinchhandler_p.h b/src/quick/handlers/qquickpinchhandler_p.h
index 0d0630d2a9..305802b6cf 100644
--- a/src/quick/handlers/qquickpinchhandler_p.h
+++ b/src/quick/handlers/qquickpinchhandler_p.h
@@ -81,8 +81,7 @@ public:
     };
     Q_ENUM(PinchOrigin)
 
-    explicit QQuickPinchHandler(QObject *parent = nullptr);
-    ~QQuickPinchHandler();
+    explicit QQuickPinchHandler(QQuickItem *parent = nullptr);
 
     qreal minimumScale() const { return m_minimumScale; }
     void setMinimumScale(qreal minimumScale);
@@ -131,28 +130,28 @@ protected:
 
 private:
     // properties
-    qreal m_activeScale;
-    qreal m_accumulatedScale;
-    qreal m_activeRotation;
-    QVector2D m_activeTranslation;
+    qreal m_activeScale = 1;
+    qreal m_accumulatedScale = 1;
+    qreal m_activeRotation = 0;
+    QVector2D m_activeTranslation = QVector2D(0, 0);
 
-    qreal m_minimumScale;
-    qreal m_maximumScale;
+    qreal m_minimumScale = -qInf();
+    qreal m_maximumScale = qInf();
 
-    qreal m_minimumRotation;
-    qreal m_maximumRotation;
+    qreal m_minimumRotation = -qInf();
+    qreal m_maximumRotation = qInf();
 
-    qreal m_minimumX;
-    qreal m_maximumX;
-    qreal m_minimumY;
-    qreal m_maximumY;
+    qreal m_minimumX = -qInf();
+    qreal m_maximumX = qInf();
+    qreal m_minimumY = -qInf();
+    qreal m_maximumY = qInf();
 
-    PinchOrigin m_pinchOrigin;
+    PinchOrigin m_pinchOrigin = PinchOrigin::PinchCenter;
 
     // internal
-    qreal m_startScale;
-    qreal m_startRotation;
-    qreal m_startDistance;
+    qreal m_startScale = 1;
+    qreal m_startRotation = 0;
+    qreal m_startDistance = 0;
     QPointF m_startPos;
 
     QVector<PointData> m_startAngles;
diff --git a/src/quick/handlers/qquickpointerdevicehandler.cpp b/src/quick/handlers/qquickpointerdevicehandler.cpp
index dfea3ec02d..24b3dc4733 100644
--- a/src/quick/handlers/qquickpointerdevicehandler.cpp
+++ b/src/quick/handlers/qquickpointerdevicehandler.cpp
@@ -57,20 +57,16 @@ QT_BEGIN_NAMESPACE
     An intermediate class (not registered as a QML type) for handlers which
     allow filtering based on device type, pointer type, or keyboard modifiers.
 */
-QQuickPointerDeviceHandler::QQuickPointerDeviceHandler(QObject *parent)
+QQuickPointerDeviceHandler::QQuickPointerDeviceHandler(QQuickItem *parent)
     : QQuickPointerHandler(*(new QQuickPointerDeviceHandlerPrivate), parent)
 {
 }
 
-QQuickPointerDeviceHandler::QQuickPointerDeviceHandler(QQuickPointerDeviceHandlerPrivate &dd, QObject *parent)
+QQuickPointerDeviceHandler::QQuickPointerDeviceHandler(QQuickPointerDeviceHandlerPrivate &dd, QQuickItem *parent)
     : QQuickPointerHandler(dd, parent)
 {
 }
 
-QQuickPointerDeviceHandler::~QQuickPointerDeviceHandler()
-{
-}
-
 QQuickPointerDevice::DeviceTypes QQuickPointerDeviceHandler::acceptedDevices() const
 {
     Q_D(const QQuickPointerDeviceHandler);
diff --git a/src/quick/handlers/qquickpointerdevicehandler_p.h b/src/quick/handlers/qquickpointerdevicehandler_p.h
index 4194769fd7..82b24369d3 100644
--- a/src/quick/handlers/qquickpointerdevicehandler_p.h
+++ b/src/quick/handlers/qquickpointerdevicehandler_p.h
@@ -65,8 +65,7 @@ class Q_AUTOTEST_EXPORT QQuickPointerDeviceHandler : public QQuickPointerHandler
     Q_PROPERTY(Qt::KeyboardModifiers acceptedModifiers READ acceptedModifiers WRITE setAcceptedModifiers NOTIFY acceptedModifiersChanged)
 
 public:
-    explicit QQuickPointerDeviceHandler(QObject *parent = nullptr);
-    ~QQuickPointerDeviceHandler();
+    explicit QQuickPointerDeviceHandler(QQuickItem *parent = nullptr);
 
     QQuickPointerDevice::DeviceTypes acceptedDevices() const;
     QQuickPointerDevice::PointerTypes acceptedPointerTypes() const;
@@ -86,7 +85,7 @@ Q_SIGNALS:
     void acceptedModifiersChanged();
 
 protected:
-    QQuickPointerDeviceHandler(QQuickPointerDeviceHandlerPrivate &dd, QObject *parent = nullptr);
+    QQuickPointerDeviceHandler(QQuickPointerDeviceHandlerPrivate &dd, QQuickItem *parent = nullptr);
 
     bool wantsPointerEvent(QQuickPointerEvent *event) override;
 
diff --git a/src/quick/handlers/qquickpointerhandler.cpp b/src/quick/handlers/qquickpointerhandler.cpp
index 91349a6ad7..0be3c05e96 100644
--- a/src/quick/handlers/qquickpointerhandler.cpp
+++ b/src/quick/handlers/qquickpointerhandler.cpp
@@ -60,12 +60,12 @@ Q_LOGGING_CATEGORY(lcPointerHandlerActive, "qt.quick.handler.active")
     events from any kind of pointing device (touch, mouse or graphics tablet).
 */
 
-QQuickPointerHandler::QQuickPointerHandler(QObject *parent)
+QQuickPointerHandler::QQuickPointerHandler(QQuickItem *parent)
   : QObject(*(new QQuickPointerHandlerPrivate), parent)
 {
 }
 
-QQuickPointerHandler::QQuickPointerHandler(QQuickPointerHandlerPrivate &dd, QObject *parent)
+QQuickPointerHandler::QQuickPointerHandler(QQuickPointerHandlerPrivate &dd, QQuickItem *parent)
   : QObject(dd, parent)
 {
 }
@@ -528,8 +528,4 @@ QQuickPointerHandlerPrivate::QQuickPointerHandlerPrivate()
 {
 }
 
-QQuickPointerHandlerPrivate::~QQuickPointerHandlerPrivate()
-{
-}
-
 QT_END_NAMESPACE
diff --git a/src/quick/handlers/qquickpointerhandler_p.h b/src/quick/handlers/qquickpointerhandler_p.h
index 9644bb959f..69a38706b3 100644
--- a/src/quick/handlers/qquickpointerhandler_p.h
+++ b/src/quick/handlers/qquickpointerhandler_p.h
@@ -73,8 +73,8 @@ class Q_QUICK_PRIVATE_EXPORT QQuickPointerHandler : public QObject, public QQmlP
     Q_PROPERTY(qreal margin READ margin WRITE setMargin NOTIFY marginChanged)
 
 public:
-    explicit QQuickPointerHandler(QObject *parent = nullptr);
-    virtual ~QQuickPointerHandler();
+    explicit QQuickPointerHandler(QQuickItem *parent = nullptr);
+    ~QQuickPointerHandler();
 
     enum GrabPermission {
         TakeOverForbidden = 0x0,
@@ -120,7 +120,7 @@ Q_SIGNALS:
     void canceled(QQuickEventPoint *point);
 
 protected:
-    QQuickPointerHandler(QQuickPointerHandlerPrivate &dd, QObject *parent);
+    QQuickPointerHandler(QQuickPointerHandlerPrivate &dd, QQuickItem *parent);
 
     void classBegin() override;
     void componentComplete() override;
diff --git a/src/quick/handlers/qquickpointerhandler_p_p.h b/src/quick/handlers/qquickpointerhandler_p_p.h
index c0b2b84a66..2ea4905643 100644
--- a/src/quick/handlers/qquickpointerhandler_p_p.h
+++ b/src/quick/handlers/qquickpointerhandler_p_p.h
@@ -67,7 +67,6 @@ public:
     static const QQuickPointerHandlerPrivate* get(const QQuickPointerHandler *q) { return q->d_func(); }
 
     QQuickPointerHandlerPrivate();
-    virtual ~QQuickPointerHandlerPrivate() override;
 
     QQuickPointerEvent *currentEvent = nullptr;
     QQuickItem *target = nullptr;
diff --git a/src/quick/handlers/qquickpointhandler.cpp b/src/quick/handlers/qquickpointhandler.cpp
index 65a7fd7b79..da19584b7a 100644
--- a/src/quick/handlers/qquickpointhandler.cpp
+++ b/src/quick/handlers/qquickpointhandler.cpp
@@ -114,16 +114,12 @@ QT_BEGIN_NAMESPACE
     \sa MultiPointTouchArea
 */
 
-QQuickPointHandler::QQuickPointHandler(QObject *parent)
+QQuickPointHandler::QQuickPointHandler(QQuickItem *parent)
     : QQuickSinglePointHandler(parent)
 {
     setIgnoreAdditionalPoints();
 }
 
-QQuickPointHandler::~QQuickPointHandler()
-{
-}
-
 bool QQuickPointHandler::wantsEventPoint(QQuickEventPoint *pt)
 {
     // On press, we want it unless a sibling of the same type also does.
diff --git a/src/quick/handlers/qquickpointhandler_p.h b/src/quick/handlers/qquickpointhandler_p.h
index 5babab0c4d..380ce1f90f 100644
--- a/src/quick/handlers/qquickpointhandler_p.h
+++ b/src/quick/handlers/qquickpointhandler_p.h
@@ -61,8 +61,7 @@ class Q_AUTOTEST_EXPORT QQuickPointHandler : public QQuickSinglePointHandler
     Q_PROPERTY(QVector2D translation READ translation NOTIFY translationChanged)
 
 public:
-    explicit QQuickPointHandler(QObject *parent = 0);
-    ~QQuickPointHandler();
+    explicit QQuickPointHandler(QQuickItem *parent = nullptr);
 
     QVector2D translation() const;
 
diff --git a/src/quick/handlers/qquicksinglepointhandler.cpp b/src/quick/handlers/qquicksinglepointhandler.cpp
index 0f8fc58bc1..fa08ced8e2 100644
--- a/src/quick/handlers/qquicksinglepointhandler.cpp
+++ b/src/quick/handlers/qquicksinglepointhandler.cpp
@@ -58,9 +58,8 @@ Q_DECLARE_LOGGING_CATEGORY(DBG_TOUCH_TARGET)
     Override handleEventPoint() to implement a single-point handler.
 */
 
-QQuickSinglePointHandler::QQuickSinglePointHandler(QObject *parent)
+QQuickSinglePointHandler::QQuickSinglePointHandler(QQuickItem *parent)
   : QQuickPointerDeviceHandler(parent)
-  , m_ignoreAdditionalPoints(false)
 {
 }
 
diff --git a/src/quick/handlers/qquicksinglepointhandler_p.h b/src/quick/handlers/qquicksinglepointhandler_p.h
index 7c225aab46..6caf4294b8 100644
--- a/src/quick/handlers/qquicksinglepointhandler_p.h
+++ b/src/quick/handlers/qquicksinglepointhandler_p.h
@@ -61,8 +61,7 @@ class Q_QUICK_PRIVATE_EXPORT QQuickSinglePointHandler : public QQuickPointerDevi
     Q_OBJECT
     Q_PROPERTY(QQuickHandlerPoint point READ point NOTIFY pointChanged)
 public:
-    explicit QQuickSinglePointHandler(QObject *parent = nullptr);
-    virtual ~QQuickSinglePointHandler() { }
+    explicit QQuickSinglePointHandler(QQuickItem *parent = nullptr);
 
     QQuickHandlerPoint point() const { return m_pointInfo; }
 
@@ -89,7 +88,7 @@ private:
 
 private:
     QQuickHandlerPoint m_pointInfo;
-    bool m_ignoreAdditionalPoints : 1;
+    bool m_ignoreAdditionalPoints = false;
 };
 
 QT_END_NAMESPACE
diff --git a/src/quick/handlers/qquicktaphandler.cpp b/src/quick/handlers/qquicktaphandler.cpp
index 1d3375314f..992bc5e438 100644
--- a/src/quick/handlers/qquicktaphandler.cpp
+++ b/src/quick/handlers/qquicktaphandler.cpp
@@ -84,13 +84,8 @@ int QQuickTapHandler::m_touchMultiTapDistanceSquared(-1);
     \sa MouseArea
 */
 
-QQuickTapHandler::QQuickTapHandler(QObject *parent)
+QQuickTapHandler::QQuickTapHandler(QQuickItem *parent)
     : QQuickSinglePointHandler(parent)
-    , m_pressed(false)
-    , m_gesturePolicy(DragThreshold)
-    , m_tapCount(0)
-    , m_longPressThreshold(-1)
-    , m_lastTapTimestamp(0.0)
 {
     if (m_mouseMultiClickDistanceSquared < 0) {
         m_multiTapInterval = qApp->styleHints()->mouseDoubleClickInterval() / 1000.0;
@@ -103,10 +98,6 @@ QQuickTapHandler::QQuickTapHandler(QObject *parent)
     }
 }
 
-QQuickTapHandler::~QQuickTapHandler()
-{
-}
-
 static bool dragOverThreshold(const QQuickEventPoint *point)
 {
     QPointF delta = point->scenePosition() - point->scenePressPosition();
diff --git a/src/quick/handlers/qquicktaphandler_p.h b/src/quick/handlers/qquicktaphandler_p.h
index b7c1895926..a4c5bf657e 100644
--- a/src/quick/handlers/qquicktaphandler_p.h
+++ b/src/quick/handlers/qquicktaphandler_p.h
@@ -75,8 +75,7 @@ public:
     };
     Q_ENUM(GesturePolicy)
 
-    explicit QQuickTapHandler(QObject *parent = nullptr);
-    ~QQuickTapHandler();
+    explicit QQuickTapHandler(QQuickItem *parent = nullptr);
 
     bool isPressed() const { return m_pressed; }
 
@@ -113,14 +112,14 @@ private:
     void updateTimeHeld();
 
 private:
-    bool m_pressed;
-    GesturePolicy m_gesturePolicy;
-    int m_tapCount;
-    int m_longPressThreshold;
-    QBasicTimer m_longPressTimer;
-    QElapsedTimer m_holdTimer;
     QPointF m_lastTapPos;
-    qreal m_lastTapTimestamp;
+    qreal m_lastTapTimestamp = 0;
+    QElapsedTimer m_holdTimer;
+    QBasicTimer m_longPressTimer;
+    int m_tapCount = 0;
+    int m_longPressThreshold = -1;
+    GesturePolicy m_gesturePolicy = GesturePolicy::DragThreshold;
+    bool m_pressed = false;
 
     static qreal m_multiTapInterval;
     static int m_mouseMultiClickDistanceSquared;