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     2 **

     3 ** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).

     4 ** All rights reserved.

     5 ** Contact: Nokia Corporation (qt-info@nokia.com)

     6 **

     7 ** This file is part of the examples of the Qt Toolkit.

     8 **

     9 ** $QT_BEGIN_LICENSE:BSD$

    10 ** You may use this file under the terms of the BSD license as follows:

    11 **

    12 ** "Redistribution and use in source and binary forms, with or without

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    39 ****************************************************************************/

    40 

    41 #include "knob.h"

    42 

    43 #include <QBrush>

    44 #include <QTouchEvent>

    45 

    46 Knob::Knob()

    47     : QGraphicsEllipseItem(-50, -50, 100, 100)

    48 {

    49     setAcceptTouchEvents(true);

    50     setBrush(Qt::lightGray);

    51 

    52     QGraphicsEllipseItem *leftItem = new QGraphicsEllipseItem(0, 0, 20, 20, this);

    53     leftItem->setPos(-40, -10);

    54     leftItem->setBrush(Qt::darkGreen);

    55 

    56     QGraphicsEllipseItem *rightItem = new QGraphicsEllipseItem(0, 0, 20, 20, this);

    57     rightItem->setPos(20, -10);

    58     rightItem->setBrush(Qt::darkRed);

    59 }

    60 

    61 bool Knob::sceneEvent(QEvent *event)

    62 {

    63     switch (event->type()) {

    64     case QEvent::TouchBegin:

    65     case QEvent::TouchUpdate:

    66     case QEvent::TouchEnd:

    67     {

    68         QTouchEvent *touchEvent = static_cast<QTouchEvent *>(event);

    69 

    70         if (touchEvent->touchPoints().count() == 2) {

    71             const QTouchEvent::TouchPoint &touchPoint1 = touchEvent->touchPoints().first();

    72             const QTouchEvent::TouchPoint &touchPoint2 = touchEvent->touchPoints().last();

    73 

    74             QLineF line1(touchPoint1.lastScenePos(), touchPoint2.lastScenePos());

    75             QLineF line2(touchPoint1.scenePos(), touchPoint2.scenePos());

    76 

    77             rotate(line2.angleTo(line1));

    78         }

    79 

    80         break;

    81     }

    82 

    83     default:

    84         return QGraphicsItem::sceneEvent(event);

    85     }

    86 

    87     return true;

    88 }