pieview.h Example File | Qt Widgets 5.12.10

- Qt 5.12
- Qt Widgets
- Chart Example
- pieview.h Example File
- Qt 5.12.10 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 = nullptr);

         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 = 0;
         int totalSize = 300;
         int pieSize = totalSize - 2 * margin;
         int validItems = 0;
         double totalValue = 0.0;
         QRubberBand *rubberBand = nullptr;
         QPoint origin;
     };

     #endif // PIEVIEW_H