digiflip.cpp Example File

 /****************************************************************************
 **
 ** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
 ** Contact: http://www.qt-project.org/
 **
 ** This file is part of the demonstration applications of the Qt Toolkit.
 **
 ** $QT_BEGIN_LICENSE:LGPL$
 ** GNU Lesser General Public License Usage
 ** This file may be used under the terms of the GNU Lesser General Public
 ** License version 2.1 as published by the Free Software Foundation and
 ** appearing in the file LICENSE.LGPL included in the packaging of this
 ** file. Please review the following information to ensure the GNU Lesser
 ** General Public License version 2.1 requirements will be met:
 ** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
 **
 ** In addition, as a special exception, Nokia gives you certain additional
 ** rights. These rights are described in the Nokia Qt 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.
 **
 ** Other Usage
 ** Alternatively, this file may be used in accordance with the terms and
 ** conditions contained in a signed written agreement between you and Nokia.
 **
 **
 **
 **
 **
 **
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/

 #include <QtCore>
 #include <QtWidgets>

 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;

         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);
         p.setRenderHint(QPainter::SmoothPixmapTransform, true);
         p.setRenderHint(QPainter::Antialiasing, true);
         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()));
         addAction(slideAction);
         addAction(flipAction);
         addAction(rotateAction);
         setContextMenuPolicy(Qt::ActionsContextMenu);
     }

     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;
     time.resize(320, 240);
     time.show();

     return app.exec();
 }