plasma-framework/declarativeimports/core/qrangemodel_p.h
Daker Fernandes Pinheiro 72f4b7c778 Add RangeModel for QtComponents
RangeModel will be used by as a logical backend to Slider and ScrollBar

Signed-off-by: Daker Fernandes Pinheiro <dakerfp@gmail.com>
2011-04-27 16:17:34 -03:00

98 lines
3.0 KiB
C++

/****************************************************************************
**
** 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 Qt Components project on Qt Labs.
**
** 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.
**
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** Nokia at qt-info@nokia.com.
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****************************************************************************/
#ifndef QRANGEMODEL_P_H
#define QRANGEMODEL_P_H
//
// W A R N I N G
// -------------
//
// This file is not part of the Qt Components API. It exists purely as an
// implementation detail. This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//
#include "qrangemodel.h"
namespace Plasma
{
class QRangeModelPrivate
{
Q_DECLARE_PUBLIC(QRangeModel)
public:
QRangeModelPrivate(QRangeModel *qq);
virtual ~QRangeModelPrivate();
void init();
qreal posatmin, posatmax;
qreal minimum, maximum, stepSize, pos, value;
uint inverted : 1;
QRangeModel *q_ptr;
inline qreal effectivePosAtMin() const {
return inverted ? posatmax : posatmin;
}
inline qreal effectivePosAtMax() const {
return inverted ? posatmin : posatmax;
}
inline qreal equivalentPosition(qreal value) const {
// Return absolute position from absolute value
const qreal valueRange = maximum - minimum;
if (valueRange == 0)
return effectivePosAtMin();
const qreal scale = (effectivePosAtMax() - effectivePosAtMin()) / valueRange;
return (value - minimum) * scale + effectivePosAtMin();
}
inline qreal equivalentValue(qreal pos) const {
// Return absolute value from absolute position
const qreal posRange = effectivePosAtMax() - effectivePosAtMin();
if (posRange == 0)
return minimum;
const qreal scale = (maximum - minimum) / posRange;
return (pos - effectivePosAtMin()) * scale + minimum;
}
qreal publicPosition(qreal position) const;
qreal publicValue(qreal value) const;
void emitValueAndPositionIfChanged(const qreal oldValue, const qreal oldPosition);
};
} // Plasma namespace
#endif // QRANGEMODEL_P_H