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# fluidlauncher.cpp Example File

demos/embedded/fluidlauncher/fluidlauncher.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.
     **
     ** $QT_BEGIN_LICENSE:LGPL$
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     ** accordance with the commercial license agreement provided with the
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     ** 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
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     ** rights. These rights are described in The Qt Company LGPL Exception
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     **
     ** 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
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     #include <QXmlStreamReader>

     #include "fluidlauncher.h"

     #define DEFAULT_INPUT_TIMEOUT 10000
     #define SIZING_FACTOR_HEIGHT 6/10
     #define SIZING_FACTOR_WIDTH 6/10

     FluidLauncher::FluidLauncher(QStringList* args)
     {
         pictureFlowWidget = new PictureFlow();
         slideShowWidget = new SlideShow();
         inputTimer = new QTimer();

         addWidget(pictureFlowWidget);
         addWidget(slideShowWidget);
         setCurrentWidget(pictureFlowWidget);
         pictureFlowWidget->setFocus();

         QRect screen_size = QApplication::desktop()->screenGeometry();

         QObject::connect(pictureFlowWidget, SIGNAL(itemActivated(int)), this, SLOT(launchApplication(int)));
         QObject::connect(pictureFlowWidget, SIGNAL(inputReceived()),    this, SLOT(resetInputTimeout()));
         QObject::connect(slideShowWidget,   SIGNAL(inputReceived()),    this, SLOT(switchToLauncher()));
         QObject::connect(inputTimer,        SIGNAL(timeout()),          this, SLOT(inputTimedout()));

         inputTimer->setSingleShot(true);
         inputTimer->setInterval(DEFAULT_INPUT_TIMEOUT);

         const int h = screen_size.height() * SIZING_FACTOR_HEIGHT;
         const int w = screen_size.width() * SIZING_FACTOR_WIDTH;
         const int hh = qMin(h, w);
         const int ww = hh / 3 * 2;
         pictureFlowWidget->setSlideSize(QSize(ww, hh));

         bool success;
         int configIndex = args->indexOf("-config");
         if ( (configIndex != -1) && (configIndex != args->count()-1) )
             success = loadConfig(args->at(configIndex+1));
         else
             success = loadConfig("config.xml");

         if (success) {
           populatePictureFlow();

           showFullScreen();
           inputTimer->start();
         } else {
             pictureFlowWidget->setAttribute(Qt::WA_DeleteOnClose, true);
             pictureFlowWidget->close();
         }

     }

     FluidLauncher::~FluidLauncher()
     {
         delete pictureFlowWidget;
         delete slideShowWidget;
     }

     bool FluidLauncher::loadConfig(QString configPath)
     {
         QFile xmlFile(configPath);

         if (!xmlFile.exists() || (xmlFile.error() != QFile::NoError)) {
             qDebug() << "ERROR: Unable to open config file " << configPath;
             return false;
         }

         slideShowWidget->clearImages();

         xmlFile.open(QIODevice::ReadOnly);
         QXmlStreamReader reader(&xmlFile);
         while (!reader.atEnd()) {
             reader.readNext();

             if (reader.isStartElement()) {
                 if (reader.name() == "demos")
                     parseDemos(reader);
                 else if(reader.name() == "slideshow")
                     parseSlideshow(reader);
             }
         }

         if (reader.hasError()) {
            qDebug() << QString("Error parsing %1 on line %2 column %3: \n%4")
                     .arg(configPath)
                     .arg(reader.lineNumber())
                     .arg(reader.columnNumber())
                     .arg(reader.errorString());
         }

         // Append an exit Item
         DemoApplication* exitItem = new DemoApplication(QString(), QLatin1String("Exit Embedded Demo"), QString(), QStringList());
         demoList.append(exitItem);

         return true;
     }

     void FluidLauncher::parseDemos(QXmlStreamReader& reader)
     {
         while (!reader.atEnd()) {
             reader.readNext();
             if (reader.isStartElement() && reader.name() == "example") {
                 QXmlStreamAttributes attrs = reader.attributes();
                 QStringRef filename = attrs.value("filename");
                 if (!filename.isEmpty()) {
                     QStringRef name = attrs.value("name");
                     QStringRef image = attrs.value("image");
                     QStringRef args = attrs.value("args");

                     DemoApplication* newDemo = new DemoApplication(
                             filename.toString(),
                             name.isEmpty() ? "Unnamed Demo" : name.toString(),
                             image.toString(),
                             args.toString().split(" "));
                     demoList.append(newDemo);
                 }
             } else if(reader.isEndElement() && reader.name() == "demos") {
                 return;
             }
         }
     }

     void FluidLauncher::parseSlideshow(QXmlStreamReader& reader)
     {
         QXmlStreamAttributes attrs = reader.attributes();

         QStringRef timeout = attrs.value("timeout");
         bool valid;
         if (!timeout.isEmpty()) {
             int t = timeout.toString().toInt(&valid);
             if (valid)
                 inputTimer->setInterval(t);
         }

         QStringRef interval = attrs.value("interval");
         if (!interval.isEmpty()) {
             int i = interval.toString().toInt(&valid);
             if (valid)
                 slideShowWidget->setSlideInterval(i);
         }

         while (!reader.atEnd()) {
             reader.readNext();
             if (reader.isStartElement()) {
                 QXmlStreamAttributes attrs = reader.attributes();
                 if (reader.name() == "imagedir") {
                     QStringRef dir = attrs.value("dir");
                     slideShowWidget->addImageDir(dir.toString());
                 } else if(reader.name() == "image") {
                     QStringRef image = attrs.value("image");
                     slideShowWidget->addImage(image.toString());
                 }
             } else if(reader.isEndElement() && reader.name() == "slideshow") {
                 return;
             }
         }

     }

     void FluidLauncher::populatePictureFlow()
     {
         pictureFlowWidget->setSlideCount(demoList.count());

         for (int i=demoList.count()-1; i>=0; --i) {
             pictureFlowWidget->setSlide(i, *(demoList[i]->getImage()));
             pictureFlowWidget->setSlideCaption(i, demoList[i]->getCaption());
         }

         pictureFlowWidget->setCurrentSlide(demoList.count()/2);
     }

     void FluidLauncher::launchApplication(int index)
     {
         // NOTE: Clearing the caches will free up more memory for the demo but will cause
         // a delay upon returning, as items are reloaded.
         //pictureFlowWidget->clearCaches();

         if (index == demoList.size() -1) {
             qApp->quit();
             return;
         }

         inputTimer->stop();

         QObject::connect(demoList[index], SIGNAL(demoFinished()), this, SLOT(demoFinished()));

         demoList[index]->launch();
     }

     void FluidLauncher::switchToLauncher()
     {
         slideShowWidget->stopShow();
         inputTimer->start();
         setCurrentWidget(pictureFlowWidget);
     }

     void FluidLauncher::resetInputTimeout()
     {
         if (inputTimer->isActive())
             inputTimer->start();
     }

     void FluidLauncher::inputTimedout()
     {
         switchToSlideshow();
     }

     void FluidLauncher::switchToSlideshow()
     {
         inputTimer->stop();
         slideShowWidget->startShow();
         setCurrentWidget(slideShowWidget);
     }

     void FluidLauncher::demoFinished()
     {
         setCurrentWidget(pictureFlowWidget);
         inputTimer->start();

         // Bring the Fluidlauncher to the foreground to allow selecting another demo
         raise();
         activateWindow();
     }

     void FluidLauncher::changeEvent(QEvent* event)
     {
         if (event->type() == QEvent::ActivationChange) {
             if (isActiveWindow()) {
                 if(currentWidget() == pictureFlowWidget) {
                     resetInputTimeout();
                 } else {
                     slideShowWidget->startShow();
                 }
             } else {
                 inputTimer->stop();
                 slideShowWidget->stopShow();
             }
         }
         QStackedWidget::changeEvent(event);
     }