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

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# fademessage.cpp Example File

effects/fademessage/fademessage.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2014 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.
     **
     **
     ** 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
     ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
     **
     ** $QT_END_LICENSE$
     **
     ****************************************************************************/

     #include "fademessage.h"

     #include <QtGui>

     FadeMessage::FadeMessage(QWidget *parent): QGraphicsView(parent)
     {
         setScene(&m_scene);
         setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
         setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);

         setupScene();

         m_animation = new QPropertyAnimation(m_effect, "strength", this);
         m_animation->setDuration(500);
         m_animation->setEasingCurve(QEasingCurve::InOutSine);
         m_animation->setStartValue(0);
         m_animation->setEndValue(1);

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

     void FadeMessage::togglePopup()
     {
         if (m_message->isVisible()) {
             m_message->setVisible(false);
             m_animation->setDirection(QAbstractAnimation::Backward);
         } else {
             m_message->setVisible(true);
             m_animation->setDirection(QAbstractAnimation::Forward);
         }
         m_animation->start();
     }

     void FadeMessage::setupScene()
     {
         QGraphicsRectItem *parent = m_scene.addRect(0, 0, 800, 600);
         parent->setPen(Qt::NoPen);
         parent->setZValue(0);

         QGraphicsPixmapItem *bg = m_scene.addPixmap(QPixmap(":/background.jpg"));
         bg->setParentItem(parent);
         bg->setZValue(-1);

         for (int i = 1; i < 5; ++i)
             for (int j = 2; j < 5; ++j) {
                 QGraphicsRectItem *item = m_scene.addRect(i * 50, (j - 1) * 50, 38, 38);
                 item->setParentItem(parent);
                 item->setZValue(1);
                 int hue = 12 * (i * 5 + j);
                 item->setBrush(QColor::fromHsv(hue, 128, 128));
             }

         QFont font;
         font.setPointSize(font.pointSize() * 2);
         font.setBold(true);
         QFontMetrics fontMetrics(font);
         int fh = fontMetrics.height();

         QString sceneText = "Qt Everywhere!";
         int sceneTextWidth = fontMetrics.width(sceneText);

         QGraphicsRectItem *block = m_scene.addRect(50, 300, sceneTextWidth, fh + 3);
         block->setPen(Qt::NoPen);
         block->setBrush(QColor(102, 153, 51));

         QGraphicsTextItem *text = m_scene.addText(sceneText, font);
         text->setDefaultTextColor(Qt::white);
         text->setPos(50, 300);
         block->setZValue(2);
         block->hide();

         text->setParentItem(block);
         m_message = block;

         m_effect = new QGraphicsColorizeEffect;
         m_effect->setColor(QColor(122, 193, 66));
         m_effect->setStrength(0);
         m_effect->setEnabled(true);
         parent->setGraphicsEffect(m_effect);

         QPushButton *press = new QPushButton;
         press->setText(tr("Press me"));
         connect(press, SIGNAL(clicked()), SLOT(togglePopup()));
         m_scene.addWidget(press);

     #if defined(Q_WS_S60) || defined(Q_WS_MAEMO_5)
         press->move(200, 210);
     #else
         press->move(300, 500);
     #endif
     }