pieview.h Example File
^{itemviews/chart/pieview.h}

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    ** Copyright (C) 2004-2006 Trolltech ASA. All rights reserved.
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    ** This file is part of the documentation of the Qt Toolkit.
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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 <QWidget>

    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 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;
        QRect selectionRect;
    };

    #endif