Implement custom bars with dynamic properties

Remove BarComponent class and instead use dynamic properties for
custom QML bar components.

Task-number: QTBUG-124507
Change-Id: Ib1c1f520ffa3770f6260b169bc6c748b4c796ab7
Reviewed-by: Tomi Korpipää <tomi.korpipaa@qt.io>

7 files changed, 111 insertions, 247 deletions

diff --git a/examples/graphs/2d/testbed/qml/testbed/CustomBars.qml b/examples/graphs/2d/testbed/qml/testbed/CustomBars.qml
index 8c1241c..c59d842 100644
--- a/examples/graphs/2d/testbed/qml/testbed/CustomBars.qml
+++ b/examples/graphs/2d/testbed/qml/testbed/CustomBars.qml
@@ -98,8 +98,12 @@ Rectangle {
             selectable: true
             barWidth: 0.8
             valuesMultiplier: barSeries.showAnimated
-            barComponent: BarComponent {
+            barComponent: Item {
                 id: comp
+                property color barColor
+                property bool barSelected
+                property real barValue
+                property string barLabel
                 anchors.alignWhenCentered: false
                 opacity: barSeries.showAnimated
                 BarImage {
diff --git a/src/graphs2d/CMakeLists.txt b/src/graphs2d/CMakeLists.txt
index 0833913..3005db6 100644
--- a/src/graphs2d/CMakeLists.txt
+++ b/src/graphs2d/CMakeLists.txt
@@ -8,7 +8,6 @@ qt_internal_extend_target(Graphs
         charthelpers_p.h
         barchart/qbarseries.cpp barchart/qbarseries.h barchart/qbarseries_p.h
         barchart/qbarset.cpp barchart/qbarset.h barchart/qbarset_p.h
-        barchart/barcomponent.cpp barchart/barcomponent_p.h
         barchart/qbarmodelmapper.cpp barchart/qbarmodelmapper.h barchart/qbarmodelmapper_p.h
         linechart/qlineseries.cpp linechart/qlineseries.h linechart/qlineseries_p.h
         piechart/qpieseries.cpp piechart/qpieseries.h piechart/qpieseries_p.h
diff --git a/src/graphs2d/barchart/barcomponent.cpp b/src/graphs2d/barchart/barcomponent.cpp
deleted file mode 100644
index fc7be14..0000000
--- a/src/graphs2d/barchart/barcomponent.cpp
+++ /dev/null
@@ -1,158 +0,0 @@
-// Copyright (C) 2024 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
-
-#include "barcomponent_p.h"
-
-QT_BEGIN_NAMESPACE
-
-/*!
-    \qmltype BarComponent
-    \inqmlmodule QtGraphs
-    \ingroup graphs_qml_2D
-    \inherits QQuickItem
-    \brief A base element for custom bar components.
-
-    In bar graphs, bars are by default rendered as rectangles with specified fill color,
-    border color etc. By using this element, it is possible to render the bars using custom
-    QML elements.
-
-    Here is an example of how to create bars that show \c backgroundImage, overlay the bar
-    with \c selectionImage once selected and render also the value of the bar into the center
-    of each bar.
-
-    \badcode
-    BarSeries {
-        barComponent: BarComponent {
-            id: comp
-            BarImage {
-                id: backgroundImage
-                anchors.fill: parent
-                source: "images/bar_background.png"
-            }
-            BarImage {
-                id: selectionImage
-                anchors.fill: parent
-                source: "images/bar_selection.png"
-                visible: comp.selected
-            }
-            Text {
-                anchors.centerIn: parent
-                text: comp.barLabel
-            }
-        }
-    }
-    \endcode
-*/
-
-BarComponent::BarComponent(QQuickItem *parent) :
-      QQuickItem(parent)
-{
-}
-
-/*!
-    \qmlproperty real BarComponent::barValue
-    The value of the bar. This value comes either from the \l{BarSet::values}.
-*/
-qreal BarComponent::barValue() const
-{
-    return m_barValue;
-}
-
-void BarComponent::setBarValue(qreal value)
-{
-    if (qFuzzyCompare(m_barValue, value))
-        return;
-    m_barValue = value;
-    Q_EMIT barValueChanged();
-}
-
-/*!
-    \qmlproperty color BarComponent::barColor
-    The fill color of the bar. This value comes either from the \l SeriesTheme
-    or from \l{BarSet::color} if the \l BarSet overrides the color.
-*/
-QColor BarComponent::barColor() const
-{
-    return m_barColor;
-}
-
-void BarComponent::setBarColor(const QColor &color)
-{
-    if (m_barColor == color)
-        return;
-    m_barColor = color;
-    Q_EMIT barColorChanged();
-}
-
-/*!
-    \qmlproperty color BarComponent::barBorderColor
-    The border color of the bar. This value comes either from the \l SeriesTheme
-    or from \l{BarSet::borderColor} if the \l BarSet overrides the color.
-*/
-QColor BarComponent::barBorderColor() const
-{
-    return m_barBorderColor;
-}
-
-void BarComponent::setBarBorderColor(const QColor &color)
-{
-    if (m_barBorderColor == color)
-        return;
-    m_barBorderColor = color;
-    Q_EMIT barBorderColorChanged();
-}
-
-/*!
-    \qmlproperty real BarComponent::barBorderWidth
-    The width of the bar border. This value comes either from the \l SeriesTheme
-    or from \l{BarSet::borderWidth} if the \l BarSet overrides the width.
-*/
-qreal BarComponent::barBorderWidth() const
-{
-    return m_barBorderWidth;
-}
-
-void BarComponent::setBarBorderWidth(qreal width)
-{
-    if (qFuzzyCompare(m_barBorderWidth, width))
-        return;
-    m_barBorderWidth = width;
-    Q_EMIT barBorderWidthChanged();
-}
-
-/*!
-    \qmlproperty string BarComponent::barLabel
-    The label of the bar. This value comes either from the \l{BarSet::label}.
-*/
-QString BarComponent::barLabel() const
-{
-    return m_barLabel;
-}
-
-void BarComponent::setBarLabel(const QString &label)
-{
-    if (m_barLabel == label)
-        return;
-    m_barLabel = label;
-    Q_EMIT barLabelChanged();
-}
-
-/*!
-    \qmlproperty bool BarComponent::barSelected
-    This value is true when the bar is selected, meaning that the bar index
-    is in \l{BarSet::selectedBars}.
-*/
-bool BarComponent::barSelected() const
-{
-    return m_barSelected;
-}
-
-void BarComponent::setBarSelected(bool selected)
-{
-    if (m_barSelected == selected)
-        return;
-    m_barSelected = selected;
-    Q_EMIT barSelectedChanged();
-}
-
-QT_END_NAMESPACE
diff --git a/src/graphs2d/barchart/barcomponent_p.h b/src/graphs2d/barchart/barcomponent_p.h
deleted file mode 100644
index 697f44c..0000000
--- a/src/graphs2d/barchart/barcomponent_p.h
+++ /dev/null
@@ -1,73 +0,0 @@
-// Copyright (C) 2024 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
-
-#ifndef BARCOMPONENT_H
-#define BARCOMPONENT_H
-
-//
-//  W A R N I N G
-//  -------------
-//
-// This file is not part of the QtGraphs 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.
-
-#include <QtGraphs/qgraphsglobal.h>
-#include <QQuickItem>
-#include <QColor>
-#include <QString>
-
-QT_BEGIN_NAMESPACE
-
-class Q_GRAPHS_EXPORT BarComponent : public QQuickItem
-{
-    Q_OBJECT
-    Q_PROPERTY(qreal barValue READ barValue NOTIFY barValueChanged)
-    Q_PROPERTY(QColor barColor READ barColor NOTIFY barColorChanged)
-    Q_PROPERTY(QColor barBorderColor READ barBorderColor NOTIFY barBorderColorChanged)
-    Q_PROPERTY(qreal barBorderWidth READ barBorderWidth NOTIFY barBorderWidthChanged)
-    Q_PROPERTY(QString barLabel READ barLabel NOTIFY barLabelChanged)
-    Q_PROPERTY(bool barSelected READ barSelected NOTIFY barSelectedChanged)
-    QML_ELEMENT
-
-public:
-    BarComponent(QQuickItem *parent = nullptr);
-
-    qreal barValue() const;
-    QColor barColor() const;
-    QColor barBorderColor() const;
-    qreal barBorderWidth() const;
-    QString barLabel() const;
-    bool barSelected() const;
-
-Q_SIGNALS:
-    void barValueChanged();
-    void barColorChanged();
-    void barBorderColorChanged();
-    void barBorderWidthChanged();
-    void barLabelChanged();
-    void barSelectedChanged();
-
-private:
-    friend class BarsRenderer;
-    void setBarValue(qreal value);
-    void setBarColor(const QColor &color);
-    void setBarBorderColor(const QColor &color);
-    void setBarBorderWidth(qreal width);
-    void setBarLabel(const QString &label);
-    void setBarSelected(bool selected);
-
-private:
-    qreal m_barValue = 0;
-    QColor m_barColor;
-    QColor m_barBorderColor;
-    qreal m_barBorderWidth = 0;
-    QString m_barLabel;
-    bool m_barSelected = false;
-};
-
-QT_END_NAMESPACE
-
-#endif // BARCOMPONENT_H
diff --git a/src/graphs2d/barchart/qbarseries.cpp b/src/graphs2d/barchart/qbarseries.cpp
index a5637f8..458974f 100644
--- a/src/graphs2d/barchart/qbarseries.cpp
+++ b/src/graphs2d/barchart/qbarseries.cpp
@@ -236,20 +236,100 @@ QT_BEGIN_NAMESPACE
 
     Default value is 6.
 */
+
 /*!
     \property QBarSeries::barComponent
     \brief A custom QML component used for visualizing each of the bars.
     Instance of this component is created for each of the bar.
-    To get access into bars properties, use \l BarComponent.
     When this is not defined, a default rectangle visualization for bars is used.
+
+    The dynamic properties available for this component are:
+
+    \table
+    \header
+        \li Type
+        \li Name
+        \li Description
+    \row
+        \li QColor
+        \li barColor
+        \li The fill color of the bar. This value comes either from the \l QGraphsTheme
+        or from \l{QBarSet::color} if the \l QBarSet overrides the color.
+    \row
+        \li QColor
+        \li barBorderColor
+        \li The border color of the bar. This value comes either from the \l QGraphsTheme
+        or from \l{QBarSet::borderColor} if the \l QBarSet overrides the color.
+    \row
+        \li qreal
+        \li barBorderWidth
+        \li The width of the bar border. This value comes either from the \l QGraphsTheme
+        or from \l{QBarSet::borderWidth} if the \l QBarSet overrides the width.
+    \row
+        \li qreal
+        \li barValue
+        \li The value of the bar. This value comes from the \l{QBarSet::values}.
+    \row
+        \li QString
+        \li barLabel
+        \li The label of the bar. This value comes from the \l{QBarSet::label}.
+    \row
+        \li bool
+        \li barSelected
+        \li This value is true when the bar is selected, meaning that the bar index
+        is in \l{QBarSet::selectedBars}.
+    \endtable
+
+    To use any of these, add property with the defined name into your custom component.
+    For example \c{"property color barColor"} and \c{"property real barValue"}.
 */
 /*!
     \qmlproperty Component BarSeries::barComponent
     A custom QML component used for visualizing each of the bars.
     Instance of this component is created for each of the bar.
-    To get access into bars properties, use \l BarComponent.
     When this is not defined, a default rectangle visualization for bars is used.
+
+    The dynamic properties available for this component are:
+
+    \table
+    \header
+        \li Type
+        \li Name
+        \li Description
+    \row
+        \li color
+        \li barColor
+        \li The fill color of the bar. This value comes either from the \l GraphsTheme
+        or from \l{BarSet::color} if the \l BarSet overrides the color.
+    \row
+        \li color
+        \li barBorderColor
+        \li The border color of the bar. This value comes either from the \l GraphsTheme
+        or from \l{BarSet::borderColor} if the \l BarSet overrides the color.
+    \row
+        \li real
+        \li barBorderWidth
+        \li The width of the bar border. This value comes either from the \l GraphsTheme
+        or from \l{BarSet::borderWidth} if the \l BarSet overrides the width.
+    \row
+        \li real
+        \li barValue
+        \li The value of the bar. This value comes from the \l{BarSet::values}.
+    \row
+        \li string
+        \li barLabel
+        \li The label of the bar. This value comes from the \l{BarSet::label}.
+    \row
+        \li bool
+        \li barSelected
+        \li This value is true when the bar is selected, meaning that the bar index
+        is in \l{BarSet::selectedBars}.
+    \endtable
+
+    To use any of these, add property with the defined name into your custom component.
+    For example \c{"property color barColor"} and \c{"property real barValue"}.
 */
+
 /*!
     \property QBarSeries::barSets
     \brief A list of sets added to the series.
diff --git a/src/graphs2d/qsgrenderer/barsrenderer.cpp b/src/graphs2d/qsgrenderer/barsrenderer.cpp
index 4bdc2fc..e0ea3af 100644
--- a/src/graphs2d/qsgrenderer/barsrenderer.cpp
+++ b/src/graphs2d/qsgrenderer/barsrenderer.cpp
@@ -6,10 +6,16 @@
 #include <private/barsrenderer_p.h>
 #include <private/qbarseries_p.h>
 #include <private/qgraphsview_p.h>
-#include <private/barcomponent_p.h>
 
 QT_BEGIN_NAMESPACE
 
+static const char* TAG_BAR_COLOR = "barColor";
+static const char* TAG_BAR_BORDER_COLOR = "barBorderColor";
+static const char* TAG_BAR_BORDER_WIDTH = "barBorderWidth";
+static const char* TAG_BAR_SELECTED = "barSelected";
+static const char* TAG_BAR_VALUE = "barValue";
+static const char* TAG_BAR_LABEL = "barLabel";
+
 BarsRenderer::BarsRenderer(QQuickItem *parent)
     : QQuickItem(parent)
 {
@@ -128,16 +134,19 @@ void BarsRenderer::updateComponents(QBarSeries *series)
                 barItem->setY(d.rect.y());
                 barItem->setWidth(d.rect.width());
                 barItem->setHeight(d.rect.height());
-                auto barComponent = qobject_cast<BarComponent *>(barItem);
-                if (barComponent) {
-                    barComponent->setBarColor(d.color);
-                    barComponent->setBarBorderColor(d.borderColor);
-                    barComponent->setBarBorderWidth(d.borderWidth);
-                    barComponent->setBarSelected(d.isSelected);
-                    barComponent->setBarValue(d.value);
-                    barComponent->setBarLabel(d.label);
-                }
-                barItem->update();
+                // Check for specific dynamic properties
+                if (barItem->property(TAG_BAR_COLOR).isValid())
+                    barItem->setProperty(TAG_BAR_COLOR, d.color);
+                if (barItem->property(TAG_BAR_BORDER_COLOR).isValid())
+                    barItem->setProperty(TAG_BAR_BORDER_COLOR, d.borderColor);
+                if (barItem->property(TAG_BAR_BORDER_WIDTH).isValid())
+                    barItem->setProperty(TAG_BAR_BORDER_WIDTH, d.borderWidth);
+                if (barItem->property(TAG_BAR_SELECTED).isValid())
+                    barItem->setProperty(TAG_BAR_SELECTED, d.isSelected);
+                if (barItem->property(TAG_BAR_VALUE).isValid())
+                    barItem->setProperty(TAG_BAR_VALUE, d.value);
+                if (barItem->property(TAG_BAR_LABEL).isValid())
+                    barItem->setProperty(TAG_BAR_LABEL, d.label);
             }
             barIndex++;
         }
diff --git a/tests/auto/qml2dtest/bars/tst_barseries.qml b/tests/auto/qml2dtest/bars/tst_barseries.qml
index 2b504f3..73472d6 100644
--- a/tests/auto/qml2dtest/bars/tst_barseries.qml
+++ b/tests/auto/qml2dtest/bars/tst_barseries.qml
@@ -37,8 +37,11 @@ Item {
 
     Component {
         id: customBarComponent
-        BarComponent {
+        Item {
             id: comp
+            property color barColor
+            property color barBorderColor
+            property real barBorderWidth
             Rectangle {
                 anchors.fill: parent
                 color: comp.barColor