kineticview.cpp

   1 #include "kineticview.h"
   2
   3 #include <QObject>
   4 #include <QDebug>
   5
   6 KineticView::KineticView( QGraphicsWidget *parent)
   7     : QGraphicsWidget( parent ), mScrollVelocity( 0 )
   8 {
   9     setFlag(QGraphicsItem::ItemIsSelectable, true);
  10     setAcceptedMouseButtons( Qt::LeftButton );
  11
  12     mViewPort = new QGraphicsWidget( this );
  13
  14     resize(300, 700);
  15 }
  16
  17 KineticView::~KineticView()
  18 {
  19     delete mWindow;
  20 }
  21
  22 void KineticView::startTimer()
  23 {
  24     QObject::startTimer( 50 );
  25 }
  26 void KineticView::setWidget( QGraphicsWidget *item)
  27 {
  28     mWindow = item;
  29     item->setParentItem( mViewPort );
  30     item->setParentLayoutItem( mViewPort );
  31
  32     QRectF tmpGeometry = mWindow->geometry();
  33     mWindow->setGeometry( QRectF(tmpGeometry.x(), tmpGeometry.y() + tmpGeometry.height(), mWindow->geometry().width(), mWindow->geometry().height()));
  34
  35     update();
  36 }
  37
  38 bool KineticView::event ( QEvent * event )
  39 {
  40     switch( event->type() ) {
  41         case QEvent::GraphicsSceneMousePress:
  42             KineticScrolling::mousePressEvent(static_cast<QGraphicsSceneMouseEvent*>(event));
  43             QGraphicsWidget::mousePressEvent(static_cast<QGraphicsSceneMouseEvent*>(event));
  44             break;
  45         case QEvent::GraphicsSceneMouseMove:
  46             KineticScrolling::mouseMoveEvent(static_cast<QGraphicsSceneMouseEvent*>(event));
  47             QGraphicsWidget::mouseMoveEvent(static_cast<QGraphicsSceneMouseEvent*>(event));
  48             mWindow->setPos(  0, qBound(   qMin(  (  qreal)0, -mWindow->size( ).height( )+mViewPort->size( ).height( )),
  49                                           mWindow->pos( ).y( ) - movement() , ( qreal)0));
  50             break;
  51         case QEvent::GraphicsSceneMouseRelease:
  52             KineticScrolling::mouseReleaseEvent(static_cast<QGraphicsSceneMouseEvent*>(event));
  53
  54             mScrollVelocity = movement();
  55             startTimer();
  56
  57             break;
  58         case QEvent::Timer:
  59             setScrollValue( mScrollVelocity );
  60             mScrollVelocity *= 0.9;
  61             if( !mScrollVelocity ) {
  62                 QTimerEvent *e = static_cast<QTimerEvent*>( event );
  63                 killTimer( e->timerId() );
  64             }
  65             break;
  66         default:
  67             break;
  68     }
  69
  70     return true;
  71 }
  72
  73 void KineticView::setScrollValue( int value )
  74 {
  75     mWindow->setPos( 0, qBound(  qMin( ( qreal)0, -mWindow->size().height()+mViewPort->size().height()),
  76                 mWindow->pos().y() - value, (qreal)0));
  77 }