1 files changed, 100 insertions, 0 deletions
diff --git a/examples/charts/chartsgallery/donutbreakdownchart.cpp b/examples/charts/chartsgallery/donutbreakdownchart.cpp
new file mode 100644
index 00000000..7faf09e4
--- /dev/null
+++ b/examples/charts/chartsgallery/donutbreakdownchart.cpp
@@ -0,0 +1,100 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
+
+#include "donutbreakdownchart.h"
+#include "donutbreakdownmainslice.h"
+
+#include <QPieLegendMarker>
+#include <QPieSeries>
+#include <QPieSlice>
+
+QT_USE_NAMESPACE
+
+//![1]
+DonutBreakdownChart::DonutBreakdownChart(QGraphicsItem *parent, Qt::WindowFlags wFlags)
+    : QChart(QChart::ChartTypeCartesian, parent, wFlags)
+{
+    // create the series for main center pie
+    m_mainSeries = new QPieSeries;
+    m_mainSeries->setPieSize(0.7);
+    QChart::addSeries(m_mainSeries);
+}
+//![1]
+
+//![2]
+void DonutBreakdownChart::addBreakdownSeries(QPieSeries *breakdownSeries, QColor color)
+{
+    QFont font("Arial", 8);
+
+    // add breakdown series as a slice to center pie
+    auto mainSlice = new DonutBreakdownMainSlice(breakdownSeries);
+    mainSlice->setName(breakdownSeries->name());
+    mainSlice->setValue(breakdownSeries->sum());
+    m_mainSeries->append(mainSlice);
+
+    // customize the slice
+    mainSlice->setBrush(color);
+    mainSlice->setLabelVisible();
+    mainSlice->setLabelColor(Qt::white);
+    mainSlice->setLabelPosition(QPieSlice::LabelInsideHorizontal);
+    mainSlice->setLabelFont(font);
+
+    // position and customize the breakdown series
+    breakdownSeries->setPieSize(0.8);
+    breakdownSeries->setHoleSize(0.7);
+    breakdownSeries->setLabelsVisible();
+    const auto slices = breakdownSeries->slices();
+    for (QPieSlice *slice : slices) {
+        color = color.lighter(115);
+        slice->setBrush(color);
+        slice->setLabelFont(font);
+    }
+
+    // add the series to the chart
+    QChart::addSeries(breakdownSeries);
+
+    // recalculate breakdown donut segments
+    recalculateAngles();
+
+    // update customize legend markers
+    updateLegendMarkers();
+}
+//![2]
+
+//![3]
+void DonutBreakdownChart::recalculateAngles()
+{
+    qreal angle = 0;
+    const auto slices = m_mainSeries->slices();
+    for (QPieSlice *slice : slices) {
+        QPieSeries *breakdownSeries = qobject_cast<DonutBreakdownMainSlice *>(slice)->breakdownSeries();
+        breakdownSeries->setPieStartAngle(angle);
+        angle += slice->percentage() * 360.0; // full pie is 360.0
+        breakdownSeries->setPieEndAngle(angle);
+    }
+}
+//![3]
+
+//![4]
+void DonutBreakdownChart::updateLegendMarkers()
+{
+    // go through all markers
+    const auto allseries = series();
+    for (QAbstractSeries *series : allseries) {
+        const auto markers = legend()->markers(series);
+        for (QLegendMarker *marker : markers) {
+            auto pieMarker = qobject_cast<QPieLegendMarker *>(marker);
+            if (series == m_mainSeries) {
+                // hide markers from main series
+                pieMarker->setVisible(false);
+            } else {
+                // modify markers from breakdown series
+                pieMarker->setLabel(QString("%1 %2%")
+                                    .arg(pieMarker->slice()->label())
+                                    .arg(pieMarker->slice()->percentage() * 100, 0, 'f', 2));
+                pieMarker->setFont(QFont("Arial", 8));
+            }
+        }
+    }
+}
+//![4]