Qt 5.9 | Qt Widgets | Chart Example | pieview.h Example File

Qt 5.9.9 Reference Documentation

# pieview.h Example File

itemviews/chart/pieview.h

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      #ifndef PIEVIEW_H
      #define PIEVIEW_H

      #include <QAbstractItemView>

      class PieView : public QAbstractItemView
      {
          Q_OBJECT

      public:
          PieView(QWidget *parent = 0);

          QRect visualRect(const QModelIndex &index) const override;
          void scrollTo(const QModelIndex &index, ScrollHint hint = EnsureVisible) override;
          QModelIndex indexAt(const QPoint &point) const override;

      protected slots:
          void dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight,
                           const QVector<int> &roles = QVector<int>()) override;
          void rowsInserted(const QModelIndex &parent, int start, int end) override;
          void rowsAboutToBeRemoved(const QModelIndex &parent, int start, int end) override;

      protected:
          bool edit(const QModelIndex &index, EditTrigger trigger, QEvent *event) override;
          QModelIndex moveCursor(QAbstractItemView::CursorAction cursorAction,
                                 Qt::KeyboardModifiers modifiers) override;

          int horizontalOffset() const override;
          int verticalOffset() const override;

          bool isIndexHidden(const QModelIndex &index) const override;

          void setSelection(const QRect&, QItemSelectionModel::SelectionFlags command) override;

          void mousePressEvent(QMouseEvent *event) override;

          void mouseMoveEvent(QMouseEvent *event) override;
          void mouseReleaseEvent(QMouseEvent *event) override;

          void paintEvent(QPaintEvent *event) override;
          void resizeEvent(QResizeEvent *event) override;
          void scrollContentsBy(int dx, int dy) override;

          QRegion visualRegionForSelection(const QItemSelection &selection) const override;

      private:
          QRect itemRect(const QModelIndex &item) const;
          QRegion itemRegion(const QModelIndex &index) const;
          int rows(const QModelIndex &index = QModelIndex()) const;
          void updateGeometries() override;

          int margin;
          int totalSize;
          int pieSize;
          int validItems;
          double totalValue;
          QPoint origin;
          QRubberBand *rubberBand;
      };

      #endif // PIEVIEW_H