src/contextview/graphicsitemfader.cpp

   1 /***************************************************************************
   2  *   Copyright (c) 2007  Nikolaj Hald Nielsen <nhnFreespirit@gmail.com>    *
   3  *                 2007  Jeff Mitchell <kde-dev@emailgoeshere.com>         *
   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  02111-1307, USA.          *
  19  ***************************************************************************/
  20
  21 #include "contextbox.h"
  22 #include "graphicsitemfader.h"
  23
  24 #include "debug.h"
  25
  26 #include <QPen>
  27 #include <QTimer>
  28
  29 using namespace Context;
  30
  31
  32 GraphicsItemFader::GraphicsItemFader( ContextBox *item )
  33     : QObject()
  34     , m_startAlpha( 0 )
  35     , m_targetAlpha( 255 )
  36     , m_fps( 0 )
  37     , m_duration( 5000 )
  38     , m_delay( 0 )
  39 {
  40     m_contentItem = item;
  41
  42     //m_fadeColor = QColor ( 255, 255, 255, 0 );
  43     m_fadeColor = m_contentItem->brush().color();
  44
  45     m_timeLine = new QTimeLine( m_duration, this );
  46     m_timeLine->setCurveShape( QTimeLine::LinearCurve );
  47     connect( m_timeLine, SIGNAL( frameChanged( int ) ), this, SLOT( fadeSlot( int ) ) );
  48     connect( m_timeLine, SIGNAL( finished() ), this, SLOT( fadeFinished() ) );
  49 }
  50
  51 GraphicsItemFader::~GraphicsItemFader()
  52 {
  53     m_timeLine->stop();
  54     fadeSlot( m_animationSteps );
  55 }
  56
  57 void GraphicsItemFader::setStartAlpha(int alpha)
  58 {
  59     m_startAlpha = alpha;
  60     m_fadeColor.setAlpha( m_startAlpha );
  61 }
  62
  63 void GraphicsItemFader::setTargetAlpha(int alpha)
  64 {
  65     m_targetAlpha = alpha;
  66 }
  67
  68 void GraphicsItemFader::setDuration(int ms)
  69 {
  70     m_duration = ms;
  71 }
  72
  73 void GraphicsItemFader::setFPS(int fps)
  74 {
  75     m_fps = fps;
  76 }
  77
  78 void GraphicsItemFader::fadeSlot(int step)
  79 {
  80     debug() << "step # " << step << " of " << m_animationSteps << endl;
  81     qreal newAlpha = m_startAlpha + ( step * m_alphaStep );
  82     m_fadeColor.setAlpha( (int)newAlpha );
  83
  84     QPen fadePen = m_contentItem->pen();
  85     QColor penColor = fadePen.color();
  86     penColor.setAlpha( (int)newAlpha );
  87     fadePen.setColor( penColor );
  88     m_contentItem->setPen( fadePen );
  89
  90     m_contentItem->titleItem()->setDefaultTextColor( QColor( 255, 255, 255, (int)newAlpha ) );
  91
  92     QLinearGradient titleBarRectGradient( QPointF( 0, 0 ), QPointF( 0, m_contentItem->titleBarRect()->boundingRect().height() ) );
  93     titleBarRectGradient.setColorAt( 0, QColor( 200, 200, 255, (int)newAlpha ) );
  94     titleBarRectGradient.setColorAt( 1, QColor( 50, 50, 255, (int)newAlpha ) );
  95     m_contentItem->titleBarRect()->setBrush( QBrush( titleBarRectGradient ) );
  96
  97     QLinearGradient contentRectGradient( QPointF( 0, 0 ), QPointF( 0, 10) );
  98     contentRectGradient.setColorAt( 0, QColor( 150, 150, 150, (int)newAlpha ) );
  99     contentRectGradient.setColorAt( 1, QColor( 255, 255, 255, (int)newAlpha ) );
 100     m_contentItem->contentRect()->setBrush( QBrush( contentRectGradient ) );
 101
 102     m_contentItem->update();
 103 }
 104
 105 void GraphicsItemFader::fadeFinished()
 106 {
 107     DEBUG_BLOCK
 108     emit( animationComplete() );
 109 }
 110
 111 void GraphicsItemFader::startFading()
 112 {
 113     QTimer::singleShot( m_delay, this, SLOT(begin()) );
 114 }
 115
 116 void GraphicsItemFader::begin()
 117 {
 118     if( m_timeLine->state() != QTimeLine::NotRunning )
 119         m_timeLine->stop();
 120
 121     int fps = ( m_fps ? m_fps : 25 );
 122
 123     //total number of animation steps;
 124     m_animationSteps = (int) ( fps * ( ( qreal ) m_duration / 1000.0 ) );
 125
 126     if( m_animationSteps == 0 )
 127         m_animationSteps = 1;
 128
 129     //how much should alpha change each step
 130     m_alphaStep = ( ( qreal ) ( m_targetAlpha - m_startAlpha ) ) / ( qreal ) m_animationSteps;
 131
 132     debug() << "Start fading, animationSteps = " << m_animationSteps << " over " << m_duration << " mseconds, alphaStep = " <<  m_alphaStep << endl;
 133
 134     m_timeLine->setDuration( m_duration );
 135     m_timeLine->setFrameRange( 0, m_animationSteps );
 136     m_timeLine->start();
 137 }
 138
 139 #include "graphicsitemfader.moc"