src/pixmapviewer.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2006 by Peter Penz                                      *
   3  *   peter.penz@gmx.at                                                     *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA          *
  19  ***************************************************************************/
  20
  21 #include "pixmapviewer.h"
  22
  23 #include <kiconloader.h>
  24 #include <QtGui/QPainter>
  25 #include <QtGui/QPixmap>
  26 #include <QtGui/QPaintEvent>
  27 #include <QtDebug>
  28
  29 PixmapViewer::PixmapViewer(QWidget* parent) :
  30     QWidget(parent)
  31    ,m_animationStep(0)
  32 {
  33     setMinimumWidth(K3Icon::SizeEnormous);
  34     setMinimumWidth(K3Icon::SizeEnormous);
  35
  36     static const int ANIMATION_DURATION = 750;
  37     m_animation.setDuration(ANIMATION_DURATION);
  38
  39     connect( &m_animation , SIGNAL(valueChanged(qreal)) , this , SLOT(update()) );
  40     connect( &m_animation , SIGNAL(finished()) , this , SLOT(finishTransition()) );
  41 }
  42
  43 PixmapViewer::~PixmapViewer()
  44 {
  45 }
  46
  47 void PixmapViewer::setPixmap(const QPixmap& pixmap)
  48 {
  49     if ( pixmap.isNull() )
  50         return;
  51
  52     m_pendingPixmap = pixmap;
  53
  54     if ( m_animation.state() == QTimeLine::NotRunning )
  55         beginTransition();
  56 }
  57
  58 void PixmapViewer::beginTransition()
  59 {
  60     Q_ASSERT( !m_pendingPixmap.isNull() );
  61     Q_ASSERT( m_nextPixmap.isNull() );
  62
  63     m_nextPixmap = m_pendingPixmap;
  64     m_pendingPixmap = QPixmap();
  65     m_animation.start();
  66 }
  67
  68 void PixmapViewer::finishTransition()
  69 {
  70     m_pixmap = m_nextPixmap;
  71     m_nextPixmap = QPixmap();
  72
  73     if ( !m_pendingPixmap.isNull() )
  74     {
  75         beginTransition();
  76     }
  77 }
  78
  79 void PixmapViewer::paintEvent(QPaintEvent* event)
  80 {
  81     QWidget::paintEvent(event);
  82
  83     QPainter painter;
  84     painter.begin(this);
  85     const int x = (width() - m_pixmap.width()) / 2;
  86     const int y = (height() - m_pixmap.height()) / 2;
  87
  88     if ( !m_nextPixmap.isNull() )
  89     {
  90         const int nextPixmapX = (width() - m_nextPixmap.width()) / 2;
  91         const int nextPixmapY = (height() - m_nextPixmap.height()) / 2;
  92
  93         painter.setOpacity( 1 - m_animation.currentValue() );
  94         painter.drawPixmap(x, y, m_pixmap);
  95         painter.setOpacity( m_animation.currentValue() );
  96         painter.drawPixmap(nextPixmapX,nextPixmapY,m_nextPixmap);
  97     }
  98     else
  99     {
 100         painter.drawPixmap(x, y, m_pixmap);
 101     }
 102
 103     painter.end();
 104 }
 105
 106 #include "pixmapviewer.moc"