gradients.h Example File
demos/gradients/gradients.h

 /****************************************************************************
 **
 ** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
 ** All rights reserved.
 ** Contact: Nokia Corporation (qt-info@nokia.com)
 **
 ** This file is part of the demonstration applications of the Qt Toolkit.
 **
 ** $QT_BEGIN_LICENSE:LGPL$
 ** Commercial Usage
 ** Licensees holding valid Qt Commercial licenses may use this file in
 ** accordance with the Qt Commercial License Agreement provided with the
 ** Software or, alternatively, in accordance with the terms contained in
 ** a written agreement between you and Nokia.
 **
 ** 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.
 **
 ** GNU General Public License Usage
 ** Alternatively, this file may be used under the terms of the GNU
 ** General Public License version 3.0 as published by the Free Software
 ** Foundation and appearing in the file LICENSE.GPL included in the
 ** packaging of this file.  Please review the following information to
 ** ensure the GNU General Public License version 3.0 requirements will be
 ** met: http://www.gnu.org/copyleft/gpl.html.
 **
 ** If you have questions regarding the use of this file, please contact
 ** Nokia at qt-info@nokia.com.
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/

 #ifndef GRADIENTS_H
 #define GRADIENTS_H

 #include "arthurwidgets.h"

 #include <QtGui>

 class HoverPoints;

 class ShadeWidget : public QWidget
 {
     Q_OBJECT
 public:
     enum ShadeType {
         RedShade,
         GreenShade,
         BlueShade,
         ARGBShade
     };

     ShadeWidget(ShadeType type, QWidget *parent);

     void setGradientStops(const QGradientStops &stops);

     void paintEvent(QPaintEvent *e);

     QSize sizeHint() const { return QSize(150, 40); }
     QPolygonF points() const;

     HoverPoints *hoverPoints() const { return m_hoverPoints; }

     uint colorAt(int x);

 signals:
     void colorsChanged();

 private:
     void generateShade();

     ShadeType m_shade_type;
     QImage m_shade;
     HoverPoints *m_hoverPoints;
     QLinearGradient m_alpha_gradient;
 };

 class GradientEditor : public QWidget
 {
     Q_OBJECT
 public:
     GradientEditor(QWidget *parent);

     void setGradientStops(const QGradientStops &stops);

 public slots:
     void pointsUpdated();

 signals:
     void gradientStopsChanged(const QGradientStops &stops);

 private:
     ShadeWidget *m_red_shade;
     ShadeWidget *m_green_shade;
     ShadeWidget *m_blue_shade;
     ShadeWidget *m_alpha_shade;
 };

 class GradientRenderer : public ArthurFrame
 {
     Q_OBJECT
 public:
     GradientRenderer(QWidget *parent);
     void paint(QPainter *p);

     QSize sizeHint() const { return QSize(400, 400); }

     HoverPoints *hoverPoints() const { return m_hoverPoints; }
     void mousePressEvent(QMouseEvent *e);

 public slots:
     void setGradientStops(const QGradientStops &stops);

     void setPadSpread() { m_spread = QGradient::PadSpread; update(); }
     void setRepeatSpread() { m_spread = QGradient::RepeatSpread; update(); }
     void setReflectSpread() { m_spread = QGradient::ReflectSpread; update(); }

     void setLinearGradient() { m_gradientType = Qt::LinearGradientPattern; update(); }
     void setRadialGradient() { m_gradientType = Qt::RadialGradientPattern; update(); }
     void setConicalGradient() { m_gradientType = Qt::ConicalGradientPattern; update(); }

 private:
     QGradientStops m_stops;
     HoverPoints *m_hoverPoints;

     QGradient::Spread m_spread;
     Qt::BrushStyle m_gradientType;
 };

 class GradientWidget : public QWidget
 {
     Q_OBJECT
 public:
     GradientWidget(QWidget *parent);

 public slots:
     void setDefault1() { setDefault(1); }
     void setDefault2() { setDefault(2); }
     void setDefault3() { setDefault(3); }
     void setDefault4() { setDefault(4); }

 private:
     void setDefault(int i);

     GradientRenderer *m_renderer;
     GradientEditor *m_editor;

     QRadioButton *m_linearButton;
     QRadioButton *m_radialButton;
     QRadioButton *m_conicalButton;
     QRadioButton *m_padSpreadButton;
     QRadioButton *m_reflectSpreadButton;
     QRadioButton *m_repeatSpreadButton;

 };

 #endif // GRADIENTS_H