kineticview.cpp

   1 /////////////////////////////////////////////////////////////////////////
   2 // kineticview.cpp                                                     //
   3 //                                                                     //
   4 // Copyright(C) 2009 Igor Trindade Oliveira <igor.oliveira@indt.org.br>//
   5 // Copyright(C) 2009 Adenilson Cavalcanti <adenilson.silva@idnt.org.br>//
   6 //                                                                     //
   7 // This library is free software; you can redistribute it and/or       //
   8 // modify it under the terms of the GNU Lesser General Public          //
   9 // License as published by the Free Software Foundation; either        //
  10 // version 2.1 of the License, or (at your option) any later version.  //
  11 //                                                                     //
  12 // This library is distributed in the hope that it will be useful,     //
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of      //
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU   //
  15 // Lesser General Public License for more details.                     //
  16 //                                                                     //
  17 // You should have received a copy of the GNU Lesser General Public    //
  18 // License along with this library; if not, write to the Free Software //
  19 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA       //
  20 // 02110-1301  USA                                                     //
  21 /////////////////////////////////////////////////////////////////////////
  22 #include "kineticview.h"
  23
  24 #include <QObject>
  25 #include <QDebug>
  26
  27 KineticView::KineticView( QGraphicsWidget *parent )
  28     : QGraphicsWidget( parent ), mScrollVelocity( 0 ), newclick( 0 ),
  29       timerID( 0 )
  30 {
  31     setFlag( QGraphicsItem::ItemIsSelectable, true );
  32     setAcceptedMouseButtons( Qt::LeftButton );
  33
  34     mViewPort = new QGraphicsWidget( this );
  35
  36     resize(300, 700);
  37 }
  38
  39 KineticView::~KineticView()
  40 {
  41     delete mWindow;
  42 }
  43
  44 void KineticView::startTimer()
  45 {
  46     timerID = QObject::startTimer( 50 );
  47 }
  48 void KineticView::setWidget( QGraphicsWidget *item)
  49 {
  50     mWindow = item;
  51     item->setParentItem( mViewPort );
  52     item->setParentLayoutItem( mViewPort );
  53
  54     QRectF tmpGeometry = mWindow->geometry();
  55     mWindow->setGeometry( QRectF( tmpGeometry.x(), tmpGeometry.y() +
  56                                   tmpGeometry.height(),
  57                                   mWindow->geometry().width(),
  58                                   mWindow->geometry().height() ) );
  59
  60     update();
  61 }
  62
  63 bool KineticView::event ( QEvent * event )
  64 {
  65     int tmp1, tmp2;
  66     switch( event->type() ) {
  67
  68         case QEvent::GraphicsSceneMousePress:
  69             newclick = 1;
  70             killTimer( timerID );
  71             timerID = 0;
  72             KineticScrolling::mousePressEvent( static_cast<QGraphicsSceneMouseEvent*>(event) );
  73             QGraphicsWidget::mousePressEvent( static_cast<QGraphicsSceneMouseEvent*>(event) );
  74             break;
  75
  76         case QEvent::GraphicsSceneMouseMove:
  77             newclick = 0;
  78             KineticScrolling::mouseMoveEvent( static_cast<QGraphicsSceneMouseEvent*>(event) );
  79             QGraphicsWidget::mouseMoveEvent( static_cast<QGraphicsSceneMouseEvent*>(event) );
  80             tmp1 = -mWindow->size().height() + mViewPort->size().height();
  81             tmp1 = qMin( 0, tmp1 );
  82             tmp2 = mWindow->pos().y() - qRound( movement() );
  83             mWindow->setPos( 0, qBound( tmp1, tmp2, 0 ) );
  84             break;
  85
  86         case QEvent::GraphicsSceneMouseRelease:
  87             newclick = 0;
  88             KineticScrolling::mouseReleaseEvent(
  89                 static_cast<QGraphicsSceneMouseEvent*>( event ) );
  90             mScrollVelocity = kin_movement();
  91             startTimer();
  92             break;
  93
  94         case QEvent::Timer:
  95             setScrollValue( mScrollVelocity );
  96             mScrollVelocity *= 0.9;
  97             if( !mScrollVelocity || newclick ) {
  98                 if ( timerID ) {
  99                     killTimer( timerID );
 100                 }
 101             }
 102             break;
 103         default:
 104             break;
 105     }
 106
 107     return true;
 108 }
 109
 110 void KineticView::setScrollValue( int value )
 111 {
 112     mWindow->setPos( 0, qBound( qMin( 0.0,
 113                                       -mWindow->size().height()
 114                                       + mViewPort->size().height() ),
 115                                 mWindow->pos().y() - value, 0.0) );
 116 }