/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef ABSTRACTSCROLLAREA_H
#define ABSTRACTSCROLLAREA_H

#include "gvbwidget.h"

class ScrollBar;
class QGraphicsGridLayout;

class AbstractScrollArea : public GvbWidget
{
    Q_OBJECT

public:

    AbstractScrollArea(QGraphicsWidget *parent = 0);
    ~AbstractScrollArea();

public:

    void setHorizontalScrollBarPolicy(Qt::ScrollBarPolicy policy);
    void setVerticalScrollBarPolicy(Qt::ScrollBarPolicy policy);
    Qt::ScrollBarPolicy verticalScrollBarPolicy() const;
    Qt::ScrollBarPolicy horizontalScrollBarPolicy() const;

    QGraphicsWidget *viewport() const;
    void setViewport(QGraphicsWidget *viewport);

    ScrollBar *verticalScrollBar() const;
    ScrollBar *horizontalScrollBar() const;

signals:

    void viewportChanged(QGraphicsWidget *viewport);

protected:

    virtual bool event(QEvent *e);
    virtual void scrollContentsBy(qreal dx, qreal dy);

private slots:

    void verticalScrollStart();
    void verticalScroll(qreal);
    void horizontalScrollStart();
    void horizontalScroll(qreal);

private:

    void adjustScrollBars();

    QGraphicsWidget *m_viewport;
    ScrollBar *m_horizontalScrollBar; 
    ScrollBar *m_verticalScrollBar; 
    Qt::ScrollBarPolicy m_verticalScrollBarPolicy;
    Qt::ScrollBarPolicy m_horizontalScrollBarPolicy;
    qreal m_prevHorizontalValue;
    qreal m_prevVerticalValue;
};

#endif // ABSTRACTSCROLLAREA_H