- Qt 5.5
- Qt Widgets
- Chart Example
- pieview.h Example File
- Qt 5.5.1 Reference Documentation

# pieview.h Example File

itemviews/chart/pieview.h

    /****************************************************************************
    **
    ** Copyright (C) 2015 The Qt Company Ltd.
    ** Contact: http://www.qt.io/licensing/
    **
    ** This file is part of the examples of the Qt Toolkit.
    **
    ** $QT_BEGIN_LICENSE:BSD$
    ** You may use this file under the terms of the BSD license as follows:
    **
    ** "Redistribution and use in source and binary forms, with or without
    ** modification, are permitted provided that the following conditions are
    ** met:
    **   * Redistributions of source code must retain the above copyright
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    **     the documentation and/or other materials provided with the
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    **     from this software without specific prior written permission.
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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 Q_DECL_OVERRIDE;
        void scrollTo(const QModelIndex &index, ScrollHint hint = EnsureVisible) Q_DECL_OVERRIDE;
        QModelIndex indexAt(const QPoint &point) const Q_DECL_OVERRIDE;

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

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

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

        bool isIndexHidden(const QModelIndex &index) const Q_DECL_OVERRIDE;

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

        void mousePressEvent(QMouseEvent *event) Q_DECL_OVERRIDE;

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

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

        QRegion visualRegionForSelection(const QItemSelection &selection) const Q_DECL_OVERRIDE;

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

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

    #endif // PIEVIEW_H