Qt 4.8: blurpicker.cpp Example File (effects/blurpicker/blurpicker.cpp)

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# blurpicker.cpp Example File

effects/blurpicker/blurpicker.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
     ** Contact: http://www.qt-project.org/legal
     **
     ** This file is part of the examples of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
     ** You may use this file under the terms of the BSD license as follows:
     **
     ** "Redistribution and use in source and binary forms, with or without
     ** modification, are permitted provided that the following conditions are
     ** met:
     **   * Redistributions of source code must retain the above copyright
     **     notice, this list of conditions and the following disclaimer.
     **   * Redistributions in binary form must reproduce the above copyright
     **     notice, this list of conditions and the following disclaimer in
     **     the documentation and/or other materials provided with the
     **     distribution.
     **   * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
     **     of its contributors may be used to endorse or promote products derived
     **     from this software without specific prior written permission.
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     **
     ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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     ****************************************************************************/

     #include "blurpicker.h"

     #include <QtGui>

     #include "blureffect.h"

     #ifndef M_PI
     #define M_PI 3.14159265358979323846
     #endif

     BlurPicker::BlurPicker(QWidget *parent): QGraphicsView(parent), m_index(0.0), m_animation(this, "index")
     {
         setBackgroundBrush(QPixmap(":/images/background.jpg"));
         setScene(new QGraphicsScene(this));

         setupScene();
         setIndex(0);

         m_animation.setDuration(400);
         m_animation.setEasingCurve(QEasingCurve::InOutSine);

         setRenderHint(QPainter::Antialiasing, true);
         setFrameStyle(QFrame::NoFrame);
     }

     qreal BlurPicker::index() const
     {
         return m_index;
     }

     void BlurPicker::setIndex(qreal index)
     {
         m_index = index;

         qreal baseline = 0;
         for (int i = 0; i < m_icons.count(); ++i) {
             QGraphicsItem *icon = m_icons[i];
             qreal a = ((i + m_index) * 2 * M_PI) / m_icons.count();
             qreal xs = 170 * sin(a);
             qreal ys = 100 * cos(a);
             QPointF pos(xs, ys);
             pos = QTransform().rotate(-20).map(pos);
             pos -= QPointF(40, 40);
             icon->setPos(pos);
             baseline = qMax(baseline, ys);
             static_cast<BlurEffect *>(icon->graphicsEffect())->setBaseLine(baseline);
         }

         scene()->update();
     }

     void BlurPicker::setupScene()
     {
         scene()->setSceneRect(-200, -120, 400, 240);

         QStringList names;
         names << ":/images/accessories-calculator.png";
         names << ":/images/accessories-text-editor.png";
         names << ":/images/help-browser.png";
         names << ":/images/internet-group-chat.png";
         names << ":/images/internet-mail.png";
         names << ":/images/internet-web-browser.png";
         names << ":/images/office-calendar.png";
         names << ":/images/system-users.png";

         for (int i = 0; i < names.count(); i++) {
             QPixmap pixmap(names[i]);
             QGraphicsPixmapItem *icon = scene()->addPixmap(pixmap);
             icon->setZValue(1);
             icon->setGraphicsEffect(new BlurEffect(icon));
             m_icons << icon;
         }

         QGraphicsPixmapItem *bg = scene()->addPixmap(QPixmap(":/images/background.jpg"));
         bg->setZValue(0);
         bg->setPos(-200, -150);
     }

     void BlurPicker::keyPressEvent(QKeyEvent *event)
     {
         int delta = 0;
         switch (event->key())
         {
         case Qt::Key_Left:
             delta = -1;
             break;
         case  Qt::Key_Right:
             delta = 1;
             break;
         default:
             break;
         }
         if (m_animation.state() == QAbstractAnimation::Stopped && delta) {
             m_animation.setEndValue(m_index + delta);
             m_animation.start();
             event->accept();
         }
     }

     void BlurPicker::resizeEvent(QResizeEvent */*event*/)
     {
     #if defined(Q_WS_S60) || defined(Q_WS_MAEMO_5) || defined(Q_WS_SIMULATOR)
         fitInView(sceneRect(), Qt::KeepAspectRatio);
     #endif
     }

     void BlurPicker::mousePressEvent(QMouseEvent *event)
     {
         int delta = 0;
         if(event->x() > (width() / 2))
         {
             delta = 1;
         }
         else
         {
             delta = -1;
         }

         if (m_animation.state() == QAbstractAnimation::Stopped && delta) {
             m_animation.setEndValue(m_index + delta);
             m_animation.start();
             event->accept();
         }
     }