src/pixmapviewer.h

   1 /***************************************************************************
   2  *   Copyright (C) 2006 by Peter Penz <peter.penz@gmx.at>                  *
   3  *                                                                         *
   4  *   This program is free software; you can redistribute it and/or modify  *
   5  *   it under the terms of the GNU General Public License as published by  *
   6  *   the Free Software Foundation; either version 2 of the License, or     *
   7  *   (at your option) any later version.                                   *
   8  *                                                                         *
   9  *   This program is distributed in the hope that it will be useful,       *
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  12  *   GNU General Public License for more details.                          *
  13  *                                                                         *
  14  *   You should have received a copy of the GNU General Public License     *
  15  *   along with this program; if not, write to the                         *
  16  *   Free Software Foundation, Inc.,                                       *
  17  *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA          *
  18  ***************************************************************************/
  19
  20 #ifndef PIXMAPVIEWER_H
  21 #define PIXMAPVIEWER_H
  22
  23 #include <QtGui/QWidget>
  24 #include <QtGui/QPixmap>
  25 #include <QtCore/QTimeLine>
  26
  27 class QPaintEvent;
  28
  29 /**
  30  * @brief Widget which shows a pixmap centered inside the boundaries.
  31  *
  32  * When the pixmap is changed, a smooth transition is done from the old pixmap
  33  * to the new pixmap.
  34  */
  35 class PixmapViewer : public QWidget
  36 {
  37     Q_OBJECT
  38
  39 public:
  40     enum Transition
  41     {
  42         /** No transition is done when the pixmap is changed. */
  43         NoTransition,
  44
  45         /**
  46          * The old pixmap is replaced by the new pixmap and the size is
  47          * adjusted smoothly to the size of the new pixmap.
  48          */
  49         DefaultTransition,
  50
  51         /**
  52          * If the old pixmap and the new pixmap have the same content, but
  53          * a different size it is recommended to use Transition::SizeTransition
  54          * instead of Transition::DefaultTransition. In this case it is assured
  55          * that the larger pixmap is used for downscaling, which leads
  56          * to an improved scaling output.
  57          */
  58         SizeTransition
  59     };
  60
  61     explicit PixmapViewer(QWidget* parent,
  62                           Transition transition = DefaultTransition);
  63
  64     virtual ~PixmapViewer();
  65     void setPixmap(const QPixmap& pixmap);
  66     const QPixmap& pixmap() const
  67     {
  68         return m_pixmap;
  69     }
  70
  71 protected:
  72     virtual void paintEvent(QPaintEvent* event);
  73
  74 private:
  75     QPixmap m_pixmap;
  76     QPixmap m_oldPixmap;
  77     QTimeLine m_animation;
  78     Transition m_transition;
  79     int m_animationStep;
  80 };
  81
  82
  83 #endif