Added candlestick chart type

  - added QCandlestickSeries
  - added QCandlestickSet
  - added QCandlestickLegendMarker
  - added model mappers
  - added Candlestick, CandlestickChartItem, CandlestickData
  - added SeriesTypeCandlestick to SeriesType enum
  - added LegendMarkerTypeCandlestick to LegendMarkerType enum
  - added candlestick chart example
  - added QML candlestick chart example
  - added candlestick tester
  - added autotests
  - added documentation

[ChangeLog][CandlestickChart] Added new chart type:
Candlestick Chart.

Task-number: QTBUG-50544
Change-Id: I17d18dfa23e0ea209bf51ab1e349585b9cb50a8f
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@qt.io>

8 files changed, 288 insertions, 10 deletions

diff --git a/src/charts/legend/legend.pri b/src/charts/legend/legend.pri
index c14cf6b0..5fcb53c7 100644
--- a/src/charts/legend/legend.pri
+++ b/src/charts/legend/legend.pri
@@ -11,8 +11,9 @@ SOURCES += \
     $$PWD/qxylegendmarker.cpp \
     $$PWD/qarealegendmarker.cpp \
     $$PWD/legendscroller.cpp \
-    $$PWD/qboxplotlegendmarker.cpp
-    
+    $$PWD/qboxplotlegendmarker.cpp \
+    $$PWD/qcandlesticklegendmarker.cpp
+
 PRIVATE_HEADERS += \
     $$PWD/legendscroller_p.h \
     $$PWD/qlegend_p.h  \
@@ -23,9 +24,9 @@ PRIVATE_HEADERS += \
     $$PWD/qbarlegendmarker_p.h \
     $$PWD/qxylegendmarker_p.h \
     $$PWD/qarealegendmarker_p.h \
-    $$PWD/qboxplotlegendmarker_p.h
-   
-    
+    $$PWD/qboxplotlegendmarker_p.h \
+    $$PWD/qcandlesticklegendmarker_p.h
+
 PUBLIC_HEADERS += \
     $$PWD/qlegend.h \
     $$PWD/qlegendmarker.h \
@@ -33,4 +34,5 @@ PUBLIC_HEADERS += \
     $$PWD/qbarlegendmarker.h \
     $$PWD/qxylegendmarker.h \
     $$PWD/qarealegendmarker.h \
-    $$PWD/qboxplotlegendmarker.h
+    $$PWD/qboxplotlegendmarker.h \
+    $$PWD/qcandlesticklegendmarker.h
diff --git a/src/charts/legend/legendmarkeritem.cpp b/src/charts/legend/legendmarkeritem.cpp
index 125199ea..1c0b5901 100644
--- a/src/charts/legend/legendmarkeritem.cpp
+++ b/src/charts/legend/legendmarkeritem.cpp
@@ -88,8 +88,14 @@ QBrush LegendMarkerItem::brush() const
 void LegendMarkerItem::setFont(const QFont &font)
 {
     m_textItem->setFont(font);
+
     QFontMetrics fn(font);
-    m_markerRect = QRectF(0,0,fn.height()/2,fn.height()/2);
+    QRectF markerRect = QRectF(0, 0, fn.height() / 2, fn.height() / 2);
+    if (m_markerRect != markerRect) {
+        m_markerRect = markerRect;
+        emit markerRectChanged();
+    }
+
     updateGeometry();
 }
 
@@ -152,6 +158,11 @@ QRectF LegendMarkerItem::boundingRect() const
     return m_boundingRect;
 }
 
+QRectF LegendMarkerItem::markerRect() const
+{
+    return m_markerRect;
+}
+
 void LegendMarkerItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
 {
     Q_UNUSED(option)
diff --git a/src/charts/legend/legendmarkeritem_p.h b/src/charts/legend/legendmarkeritem_p.h
index 870cfb2e..c3371742 100644
--- a/src/charts/legend/legendmarkeritem_p.h
+++ b/src/charts/legend/legendmarkeritem_p.h
@@ -56,7 +56,7 @@ class LegendMarkerItem : public QGraphicsObject, public QGraphicsLayoutItem
     Q_OBJECT
     Q_INTERFACES(QGraphicsLayoutItem)
 public:
-    explicit LegendMarkerItem(QLegendMarkerPrivate *marker, QGraphicsObject *parent = 0);
+    explicit LegendMarkerItem(QLegendMarkerPrivate *marker, QGraphicsObject *parent = nullptr);
     ~LegendMarkerItem();
 
     void setPen(const QPen &pen);
@@ -76,8 +76,9 @@ public:
 
     void setGeometry(const QRectF &rect);
     QRectF boundingRect() const;
+    QRectF markerRect() const;
 
-    void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = 0);
+    void paint(QPainter *painter, const QStyleOptionGraphicsItem *option,QWidget *widget = nullptr);
     QSizeF sizeHint (Qt::SizeHint which, const QSizeF &constraint) const;
 
     void hoverEnterEvent(QGraphicsSceneHoverEvent *event);
@@ -85,6 +86,10 @@ public:
 
     QString displayedLabel() const;
     void setToolTip(const QString &tooltip);
+
+Q_SIGNALS:
+    void markerRectChanged();
+
 protected:
     QLegendMarkerPrivate *m_marker; // Knows
     QRectF m_markerRect;
diff --git a/src/charts/legend/qcandlesticklegendmarker.cpp b/src/charts/legend/qcandlesticklegendmarker.cpp
new file mode 100644
index 00000000..97208e3c
--- /dev/null
+++ b/src/charts/legend/qcandlesticklegendmarker.cpp
@@ -0,0 +1,125 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt Charts module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 or (at your option) any later version
+** approved by the KDE Free Qt Foundation. The licenses are as published by
+** the Free Software Foundation and appearing in the file LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtCharts/QCandlestickLegendMarker>
+#include <private/legendmarkeritem_p.h>
+#include <private/qcandlesticklegendmarker_p.h>
+#include <private/qcandlestickseries_p.h>
+
+QT_CHARTS_BEGIN_NAMESPACE
+
+QCandlestickLegendMarker::QCandlestickLegendMarker(QCandlestickSeries *series, QLegend *legend,
+                                                   QObject *parent)
+    : QLegendMarker(*new QCandlestickLegendMarkerPrivate(this, series, legend), parent)
+{
+    Q_D(QCandlestickLegendMarker);
+
+    d->updated();
+}
+
+QCandlestickLegendMarker::~QCandlestickLegendMarker()
+{
+}
+
+QLegendMarker::LegendMarkerType QCandlestickLegendMarker::type()
+{
+    return LegendMarkerTypeCandlestick;
+}
+
+QCandlestickSeries* QCandlestickLegendMarker::series()
+{
+    Q_D(QCandlestickLegendMarker);
+
+    return d->m_series;
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+QCandlestickLegendMarkerPrivate::QCandlestickLegendMarkerPrivate(QCandlestickLegendMarker *q,
+                                                                 QCandlestickSeries *series,
+                                                                 QLegend *legend)
+    : QLegendMarkerPrivate(q, legend),
+      q_ptr(q),
+      m_series(series)
+{
+    QObject::connect(m_item, SIGNAL(markerRectChanged()), this, SLOT(updated()));
+    QObject::connect(m_series, SIGNAL(nameChanged()), this, SLOT(updated()));
+    QObject::connect(m_series->d_func(), SIGNAL(updated()), this, SLOT(updated()));
+}
+
+QCandlestickLegendMarkerPrivate::~QCandlestickLegendMarkerPrivate()
+{
+}
+
+QAbstractSeries* QCandlestickLegendMarkerPrivate::series()
+{
+    return m_series;
+}
+
+QObject* QCandlestickLegendMarkerPrivate::relatedObject()
+{
+    return m_series;
+}
+
+void QCandlestickLegendMarkerPrivate::updated()
+{
+    bool labelChanged = false;
+    bool brushChanged = false;
+
+    if (!m_customLabel && (m_item->label() != m_series->name())) {
+        m_item->setLabel(m_series->name());
+        labelChanged = true;
+    }
+    if (!m_customBrush) {
+        QLinearGradient gradient;
+        gradient.setStart(0.0, 0.0);
+        gradient.setFinalStop(m_item->markerRect().width(), m_item->markerRect().height());
+        gradient.setColorAt(0.0, m_series->increasingColor());
+        gradient.setColorAt(0.49, m_series->increasingColor());
+        gradient.setColorAt(0.50, m_series->decreasingColor());
+        gradient.setColorAt(1.0, m_series->decreasingColor());
+
+        QBrush brush(gradient);
+        if (m_item->brush() != brush) {
+            m_item->setBrush(brush);
+            brushChanged = true;
+        }
+    }
+    invalidateLegend();
+
+    if (labelChanged)
+        emit q_ptr->labelChanged();
+    if (brushChanged)
+        emit q_ptr->brushChanged();
+}
+
+#include "moc_qcandlesticklegendmarker.cpp"
+#include "moc_qcandlesticklegendmarker_p.cpp"
+
+QT_CHARTS_END_NAMESPACE
diff --git a/src/charts/legend/qcandlesticklegendmarker.h b/src/charts/legend/qcandlesticklegendmarker.h
new file mode 100644
index 00000000..dad57c4f
--- /dev/null
+++ b/src/charts/legend/qcandlesticklegendmarker.h
@@ -0,0 +1,61 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt Charts module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 or (at your option) any later version
+** approved by the KDE Free Qt Foundation. The licenses are as published by
+** the Free Software Foundation and appearing in the file LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QCANDLESTICKLEGENDMARKER_H
+#define QCANDLESTICKLEGENDMARKER_H
+
+#include <QtCharts/QCandlestickSeries>
+#include <QtCharts/QLegendMarker>
+
+QT_CHARTS_BEGIN_NAMESPACE
+
+class QCandlestickLegendMarkerPrivate;
+
+class QT_CHARTS_EXPORT QCandlestickLegendMarker : public QLegendMarker
+{
+    Q_OBJECT
+
+public:
+    explicit QCandlestickLegendMarker(QCandlestickSeries *series, QLegend *legend,
+                                      QObject *parent = nullptr);
+    virtual ~QCandlestickLegendMarker();
+
+    virtual LegendMarkerType type();
+
+    // Related series
+    virtual QCandlestickSeries* series();
+
+private:
+    Q_DECLARE_PRIVATE(QCandlestickLegendMarker)
+    Q_DISABLE_COPY(QCandlestickLegendMarker)
+};
+
+QT_CHARTS_END_NAMESPACE
+
+#endif // QCANDLESTICKLEGENDMARKER_H
diff --git a/src/charts/legend/qcandlesticklegendmarker_p.h b/src/charts/legend/qcandlesticklegendmarker_p.h
new file mode 100644
index 00000000..1c786b3a
--- /dev/null
+++ b/src/charts/legend/qcandlesticklegendmarker_p.h
@@ -0,0 +1,72 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt Charts module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 or (at your option) any later version
+** approved by the KDE Free Qt Foundation. The licenses are as published by
+** the Free Software Foundation and appearing in the file LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt Chart API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+
+#ifndef QCANDLESTICKLEGENDMARKER_P_H
+#define QCANDLESTICKLEGENDMARKER_P_H
+
+#include <private/qlegendmarker_p.h>
+
+QT_CHARTS_BEGIN_NAMESPACE
+
+class QCandlestickLegendMarker;
+class QCandlestickSeries;
+
+class QCandlestickLegendMarkerPrivate : public QLegendMarkerPrivate
+{
+    Q_OBJECT
+public:
+    explicit QCandlestickLegendMarkerPrivate(QCandlestickLegendMarker *q,
+                                             QCandlestickSeries *series, QLegend *legend);
+    virtual ~QCandlestickLegendMarkerPrivate();
+
+    virtual QAbstractSeries *series();
+    virtual QObject *relatedObject();
+
+public Q_SLOTS:
+    virtual void updated();
+
+private:
+    QCandlestickLegendMarker *q_ptr;
+    QCandlestickSeries *m_series;
+
+    Q_DECLARE_PUBLIC(QCandlestickLegendMarker)
+};
+
+QT_CHARTS_END_NAMESPACE
+
+#endif // QCANDLESTICKLEGENDMARKER_P_H
diff --git a/src/charts/legend/qlegendmarker.cpp b/src/charts/legend/qlegendmarker.cpp
index 8d240876..b9da4852 100644
--- a/src/charts/legend/qlegendmarker.cpp
+++ b/src/charts/legend/qlegendmarker.cpp
@@ -63,6 +63,7 @@ QT_CHARTS_BEGIN_NAMESPACE
     \value LegendMarkerTypePie
     \value LegendMarkerTypeXY
     \value LegendMarkerTypeBoxPlot
+    \value LegendMarkerTypeCandlestick
 */
 
 /*!
diff --git a/src/charts/legend/qlegendmarker.h b/src/charts/legend/qlegendmarker.h
index 142b7e45..86721440 100644
--- a/src/charts/legend/qlegendmarker.h
+++ b/src/charts/legend/qlegendmarker.h
@@ -52,7 +52,8 @@ public:
         LegendMarkerTypeBar,
         LegendMarkerTypePie,
         LegendMarkerTypeXY,
-        LegendMarkerTypeBoxPlot
+        LegendMarkerTypeBoxPlot,
+        LegendMarkerTypeCandlestick
     };
 
     Q_PROPERTY(QString label READ label WRITE setLabel NOTIFY labelChanged)