Qt 5.7 | Qt Data Visualization | Custom Proxy Example | variantbardataproxy.h Example File

Qt 5.7.1 Reference Documentation

# variantbardataproxy.h Example File

customproxy/variantbardataproxy.h

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      #ifndef VARIANTBARDATAPROXY_H
      #define VARIANTBARDATAPROXY_H

      #include "qbardataproxy.h"
      #include "variantdataset.h"
      #include "variantbardatamapping.h"
      #include <QtCore/QStringList>
      #include <QtCore/QMap>
      #include <QtCore/QPointer>

      using namespace QtDataVisualization;

      class VariantBarDataProxy : public QBarDataProxy
      {
          Q_OBJECT

      public:
          explicit VariantBarDataProxy();
          explicit VariantBarDataProxy(VariantDataSet *newSet, VariantBarDataMapping *mapping);
          virtual ~VariantBarDataProxy();

          // Doesn't gain ownership of the dataset, but does connect to it to listen for data changes.
          void setDataSet(VariantDataSet *newSet);
          VariantDataSet *dataSet();

          // Map key (row, column, value) to value index in data item (VariantItem).
          // Doesn't gain ownership of mapping, but does connect to it to listen for mapping changes.
          // Modifying mapping that is set to proxy will trigger dataset re-resolving.
          void setMapping(VariantBarDataMapping *mapping);
          VariantBarDataMapping *mapping();

      public Q_SLOTS:
          void handleItemsAdded(int index, int count);
          void handleDataCleared();
          void handleMappingChanged();

      private:
          void resolveDataSet();

          QPointer<VariantDataSet> m_dataSet;
          QPointer<VariantBarDataMapping> m_mapping;

          Q_DISABLE_COPY(VariantBarDataProxy)
      };

      #endif