Custom Proxy Example

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 #ifndef RAINFALLGRAPH_H
 #define RAINFALLGRAPH_H

 #include "variantbardataproxy.h"
 #include <QtDataVisualization/q3dbars.h>

 using namespace QtDataVisualization;

 class RainfallGraph : public QObject
 {
     Q_OBJECT
 public:
     explicit RainfallGraph(Q3DBars *rainfall);
     ~RainfallGraph();

     void addDataSet();
     void start();

 private:

     void updateYearsList(int start, int end);
     Q3DBars *m_graph;
     int m_columnCount;
     int m_rowCount;
     QStringList m_years;
     QStringList m_numericMonths;
     VariantBarDataProxy *m_proxy;
     VariantBarDataMapping *m_mapping;
     VariantDataSet *m_dataSet;
 };

 #endif