Qt Reference Documentation

# pieview.h Example File

itemviews/chart/pieview.h

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     #ifndef PIEVIEW_H
     #define PIEVIEW_H

     #include <QAbstractItemView>
     #include <QFont>
     #include <QItemSelection>
     #include <QItemSelectionModel>
     #include <QModelIndex>
     #include <QRect>
     #include <QSize>
     #include <QPoint>
     #include <QWidget>

     class QRubberBand;

     class PieView : public QAbstractItemView
     {
         Q_OBJECT

     public:
         PieView(QWidget *parent = 0);

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

     protected slots:
         void dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight);
         void rowsInserted(const QModelIndex &parent, int start, int end);
         void rowsAboutToBeRemoved(const QModelIndex &parent, int start, int end);

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

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

         bool isIndexHidden(const QModelIndex &index) const;

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

         void mousePressEvent(QMouseEvent *event);

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

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

         QRegion visualRegionForSelection(const QItemSelection &selection) const;

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

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

     #endif