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# digiflip.cpp Example File

demos/embedded/digiflip/digiflip.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2015 The Qt Company Ltd.
     ** Contact: http://www.qt.io/licensing/
     **
     ** This file is part of the demonstration applications of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:LGPL$
     ** Commercial License Usage
     ** Licensees holding valid commercial Qt licenses may use this file in
     ** accordance with the commercial license agreement provided with the
     ** Software or, alternatively, in accordance with the terms contained in
     ** a written agreement between you and The Qt Company. For licensing terms
     ** and conditions see http://www.qt.io/terms-conditions. For further
     ** information use the contact form at http://www.qt.io/contact-us.
     **
     ** GNU Lesser General Public License Usage
     ** Alternatively, this file may be used under the terms of the GNU Lesser
     ** General Public License version 2.1 or version 3 as published by the Free
     ** Software Foundation and appearing in the file LICENSE.LGPLv21 and
     ** LICENSE.LGPLv3 included in the packaging of this file. Please review the
     ** following information to ensure the GNU Lesser General Public License
     ** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
     ** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
     **
     ** As a special exception, The Qt Company gives you certain additional
     ** rights. These rights are described in The Qt Company LGPL Exception
     ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
     **
     ** GNU General Public License Usage
     ** Alternatively, this file may be used under the terms of the GNU
     ** General Public License version 3.0 as published by the Free Software
     ** Foundation and appearing in the file LICENSE.GPL included in the
     ** packaging of this file.  Please review the following information to
     ** ensure the GNU General Public License version 3.0 requirements will be
     ** met: http://www.gnu.org/copyleft/gpl.html.
     **
     ** $QT_END_LICENSE$
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     ****************************************************************************/

     #include <QtCore>
     #include <QtGui>

     class Digits: public QWidget
     {
         Q_OBJECT

     public:

         enum {
             Slide,
             Flip,
             Rotate
         };

         Digits(QWidget *parent)
             : QWidget(parent)
             , m_number(0)
             , m_transition(Slide)
         {
             setAttribute(Qt::WA_OpaquePaintEvent, true);
             setAttribute(Qt::WA_NoSystemBackground, true);
             connect(&m_animator, SIGNAL(frameChanged(int)), SLOT(update()));
             m_animator.setFrameRange(0, 100);
             m_animator.setDuration(600);
             m_animator.setCurveShape(QTimeLine::EaseInOutCurve);
         }

         void setTransition(int tr) {
             m_transition = tr;
         }

         int transition() const {
             return m_transition;
         }

         void setNumber(int n) {
             if (m_number != n) {
                 m_number = qBound(0, n, 99);
                 preparePixmap();
                 update();
             }
         }

         void flipTo(int n) {
             if (m_number != n) {
                 m_number = qBound(0, n, 99);
                 m_lastPixmap = m_pixmap;
                 preparePixmap();
                 m_animator.stop();
                 m_animator.start();
             }
         }

     protected:

         void drawFrame(QPainter *p, const QRect &rect) {
             p->setPen(Qt::NoPen);
             QLinearGradient gradient(rect.topLeft(), rect.bottomLeft());
             gradient.setColorAt(0.00, QColor(245, 245, 245));
             gradient.setColorAt(0.49, QColor(192, 192, 192));
             gradient.setColorAt(0.51, QColor(245, 245, 245));
             gradient.setColorAt(1.00, QColor(192, 192, 192));
             p->setBrush(gradient);
             QRect r = rect;
             p->drawRoundedRect(r, 15, 15, Qt::RelativeSize);
             r.adjust(1, 4, -1, -4);
             p->setPen(QColor(181, 181, 181));
             p->setBrush(Qt::NoBrush);
             p->drawRoundedRect(r, 15, 15, Qt::RelativeSize);
             p->setPen(QColor(159, 159, 159));
             int y = rect.top() + rect.height() / 2 - 1;
             p->drawLine(rect.left(), y, rect.right(), y);
         }

         QPixmap drawDigits(int n, const QRect &rect) {

             int scaleFactor = 2;
     #if defined(Q_OS_SYMBIAN) || defined(Q_OS_WINCE_WM)
             if (rect.height() > 240)
                 scaleFactor = 1;
     #endif

             QString str = QString::number(n);
             if (str.length() == 1)
                 str.prepend("0");

             QFont font;
             font.setFamily("Helvetica");
             int fontHeight = scaleFactor * 0.55 * rect.height();
             font.setPixelSize(fontHeight);
             font.setBold(true);

             QPixmap pixmap(rect.size() * scaleFactor);
             pixmap.fill(Qt::transparent);

             QLinearGradient gradient(QPoint(0, 0), QPoint(0, pixmap.height()));
             gradient.setColorAt(0.00, QColor(128, 128, 128));
             gradient.setColorAt(0.49, QColor(64, 64, 64));
             gradient.setColorAt(0.51, QColor(128, 128, 128));
             gradient.setColorAt(1.00, QColor(16, 16, 16));

             QPainter p;
             p.begin(&pixmap);
             p.setFont(font);
             QPen pen;
             pen.setBrush(QBrush(gradient));
             p.setPen(pen);
             p.drawText(pixmap.rect(), Qt::AlignCenter, str);
             p.end();

             return pixmap.scaledToWidth(width(), Qt::SmoothTransformation);
         }

         void preparePixmap() {
             m_pixmap = QPixmap(size());
             m_pixmap.fill(Qt::transparent);
             QPainter p;
             p.begin(&m_pixmap);
             p.drawPixmap(0, 0, drawDigits(m_number, rect()));
             p.end();
         }

         void resizeEvent(QResizeEvent*) {
             preparePixmap();
             update();
         }

         void paintStatic() {
             QPainter p(this);
             p.fillRect(rect(), Qt::black);

             int pad = width() / 10;
             drawFrame(&p, rect().adjusted(pad, pad, -pad, -pad));
             p.drawPixmap(0, 0, m_pixmap);
         }

         void paintSlide() {
             QPainter p(this);
             p.fillRect(rect(), Qt::black);

             int pad = width() / 10;
             QRect fr = rect().adjusted(pad, pad, -pad, -pad);
             drawFrame(&p, fr);
             p.setClipRect(fr);

             int y = height() * m_animator.currentFrame() / 100;
             p.drawPixmap(0, y, m_lastPixmap);
             p.drawPixmap(0, y - height(), m_pixmap);
         }

         void paintFlip() {
             QPainter p(this);
     #if !defined(Q_OS_SYMBIAN) && !defined(Q_OS_WINCE_WM)
             p.setRenderHint(QPainter::SmoothPixmapTransform, true);
             p.setRenderHint(QPainter::Antialiasing, true);
     #endif
             p.fillRect(rect(), Qt::black);

             int hw = width() / 2;
             int hh = height() / 2;

             // behind is the new pixmap
             int pad = width() / 10;
             QRect fr = rect().adjusted(pad, pad, -pad, -pad);
             drawFrame(&p, fr);
             p.drawPixmap(0, 0, m_pixmap);

             int index = m_animator.currentFrame();

             if (index <= 50) {

                 // the top part of the old pixmap is flipping
                 int angle = -180 * index / 100;
                 QTransform transform;
                 transform.translate(hw, hh);
                 transform.rotate(angle, Qt::XAxis);
                 p.setTransform(transform);
                 drawFrame(&p, fr.adjusted(-hw, -hh, -hw, -hh));
                 p.drawPixmap(-hw, -hh, m_lastPixmap);

                 // the bottom part is still the old pixmap
                 p.resetTransform();
                 p.setClipRect(0, hh, width(), hh);
                 drawFrame(&p, fr);
                 p.drawPixmap(0, 0, m_lastPixmap);
             } else {

                 p.setClipRect(0, hh, width(), hh);

                 // the bottom part is still the old pixmap
                 drawFrame(&p, fr);
                 p.drawPixmap(0, 0, m_lastPixmap);

                 // the bottom part of the new pixmap is flipping
                 int angle = 180 - 180 * m_animator.currentFrame() / 100;
                 QTransform transform;
                 transform.translate(hw, hh);
                 transform.rotate(angle, Qt::XAxis);
                 p.setTransform(transform);
                 drawFrame(&p, fr.adjusted(-hw, -hh, -hw, -hh));
                 p.drawPixmap(-hw, -hh, m_pixmap);

             }

         }

         void paintRotate() {
             QPainter p(this);

             int pad = width() / 10;
             QRect fr = rect().adjusted(pad, pad, -pad, -pad);
             drawFrame(&p, fr);
             p.setClipRect(fr);

             int angle1 = -180 * m_animator.currentFrame() / 100;
             int angle2 = 180 - 180 * m_animator.currentFrame() / 100;
             int angle = (m_animator.currentFrame() <= 50) ? angle1 : angle2;
             QPixmap pix = (m_animator.currentFrame() <= 50) ? m_lastPixmap : m_pixmap;

             QTransform transform;
             transform.translate(width() / 2, height() / 2);
             transform.rotate(angle, Qt::XAxis);

             p.setTransform(transform);
             p.setRenderHint(QPainter::SmoothPixmapTransform, true);
             p.drawPixmap(-width() / 2, -height() / 2, pix);
         }

         void paintEvent(QPaintEvent *event) {
             Q_UNUSED(event);
             if (m_animator.state() == QTimeLine::Running) {
                 if (m_transition == Slide)
                     paintSlide();
                 if (m_transition == Flip)
                     paintFlip();
                 if (m_transition == Rotate)
                     paintRotate();
             } else {
                 paintStatic();
             }
         }

     private:
         int m_number;
         int m_transition;
         QPixmap m_pixmap;
         QPixmap m_lastPixmap;
         QTimeLine m_animator;
     };

     class DigiFlip : public QMainWindow
     {
         Q_OBJECT

     public:
         DigiFlip(QWidget *parent = 0)
             : QMainWindow(parent)
         {
             m_hour = new Digits(this);
             m_hour->show();
             m_minute = new Digits(this);
             m_minute->show();

             QPalette pal = palette();
             pal.setColor(QPalette::Window, Qt::black);
             setPalette(pal);

             m_ticker.start(1000, this);
             QTime t = QTime::currentTime();
             m_hour->setNumber(t.hour());
             m_minute->setNumber(t.minute());
             updateTime();

             QAction *slideAction = new QAction("&Slide", this);
             QAction *flipAction = new QAction("&Flip", this);
             QAction *rotateAction = new QAction("&Rotate", this);
             connect(slideAction, SIGNAL(triggered()), SLOT(chooseSlide()));
             connect(flipAction, SIGNAL(triggered()), SLOT(chooseFlip()));
             connect(rotateAction, SIGNAL(triggered()), SLOT(chooseRotate()));
     #if defined(Q_OS_SYMBIAN) || defined(Q_OS_WINCE_WM)
             menuBar()->addAction(slideAction);
             menuBar()->addAction(flipAction);
             menuBar()->addAction(rotateAction);
     #else
             addAction(slideAction);
             addAction(flipAction);
             addAction(rotateAction);
             setContextMenuPolicy(Qt::ActionsContextMenu);
     #endif
         }

         void updateTime() {
             QTime t = QTime::currentTime();
             m_hour->flipTo(t.hour());
             m_minute->flipTo(t.minute());
             QString str = t.toString("hh:mm:ss");
             str.prepend(": ");
             if (m_hour->transition() == Digits::Slide)
                 str.prepend("Slide");
             if (m_hour->transition() == Digits::Flip)
                 str.prepend("Flip");
             if (m_hour->transition() == Digits::Rotate)
                 str.prepend("Rotate");
             setWindowTitle(str);
         }

         void switchTransition(int delta) {
             int i = (m_hour->transition() + delta + 3) % 3;
             m_hour->setTransition(i);
             m_minute->setTransition(i);
             updateTime();
         }

     protected:
         void resizeEvent(QResizeEvent*) {
             int digitsWidth = width() / 2;
             int digitsHeight = digitsWidth * 1.2;

             int y = (height() - digitsHeight) / 3;

             m_hour->resize(digitsWidth, digitsHeight);
             m_hour->move(0, y);

             m_minute->resize(digitsWidth, digitsHeight);
             m_minute->move(width() / 2, y);
         }

         void timerEvent(QTimerEvent*) {
             updateTime();
         }

         void keyPressEvent(QKeyEvent *event) {
             if (event->key() == Qt::Key_Right) {
                 switchTransition(1);
                 event->accept();
             }
             if (event->key() == Qt::Key_Left) {
                 switchTransition(-1);
                 event->accept();
             }
         }

     private slots:
         void chooseSlide() {
             m_hour->setTransition(0);
             m_minute->setTransition(0);
             updateTime();
         }

         void chooseFlip() {
             m_hour->setTransition(1);
             m_minute->setTransition(1);
             updateTime();
         }

         void chooseRotate() {
             m_hour->setTransition(2);
             m_minute->setTransition(2);
             updateTime();
         }

     private:
         QBasicTimer m_ticker;
         Digits *m_hour;
         Digits *m_minute;
     };

     #include "digiflip.moc"

     int main(int argc, char *argv[])
     {
         QApplication app(argc, argv);

         DigiFlip time;
     #if defined(Q_OS_SYMBIAN) || defined(Q_OS_WINCE_WM)
         time.showMaximized();
     #else
         time.resize(320, 240);
         time.show();
     #endif

         return app.exec();
     }