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# main.cpp Example File

gestures/imagegestures/main.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2015 The Qt Company Ltd.
     ** Contact: http://www.qt.io/licensing/
     **
     ** 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.
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     **     contributors may be used to endorse or promote products derived
     **     from this software without specific prior written permission.
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     **
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     ** "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 <QtGui>

     #include "mainwidget.h"
     #include "imagewidget.h"

     static const char helpText[] =
     "Usage: ./imagegestures [options] Directory\n\
     Image Gestures Example\n\
     \n\
     Options:\n\
       --no-pan    Disable pan gesture\n\
       --no-pinch  Disable pinch gesture\n\
       --no-swipe  Disable swipe gesture\n\
       -h, --help  Displays this help.\n\
     \n\
     Arguments:\n\
       Directory   Directory to display\n";

     static void showHelp(const QString errorMessage = QString())
     {
         QString text;
         QTextStream str(&text);
         str << "<html><head/><body>";
         if (!errorMessage.isEmpty())
             str << "<p>" << errorMessage << "</p>";
         str << "<pre>" << helpText << "</pre></body></html>";
         QMessageBox box(errorMessage.isEmpty() ? QMessageBox::Information : QMessageBox::Warning,
                         QLatin1String("Image Gestures Example"), text,
                         QMessageBox::Ok);
         box.exec();
     }

     int main(int argc, char *argv[])
     {
         QApplication app(argc, argv);
         QCoreApplication::setApplicationVersion(QT_VERSION_STR);
         QCoreApplication::setApplicationName(QLatin1String("imagegestures"));

         QStringList arguments = QApplication::arguments();

         QString directory;
         QList<Qt::GestureType> gestures;
         gestures << Qt::PanGesture << Qt::PinchGesture << Qt::SwipeGesture;
         for (int a = 1; a < arguments.size(); ++a) {
             const QString &argument = arguments.at(a);
             if (argument.startsWith(QLatin1Char('-'))) {
                 if (argument == QLatin1String("--no-pan"))
                     gestures.removeAll(Qt::PanGesture);
                 else if (argument == QLatin1String("--no-pinch"))
                     gestures.removeAll(Qt::PinchGesture);
                 else if (argument == QLatin1String("--no-swipe"))
                     gestures.removeAll(Qt::SwipeGesture);
                 else if (argument == QLatin1String("--verbose"))
                     ImageWidget::setVerbose(true);
                 else if (argument == QLatin1String("-h") || argument == QLatin1String("--help")) {
                     showHelp();
                     return 0;
                 } else {
                     showHelp(QLatin1String("Invalid option: ") + argument);
                     return 1;
                 }
             } else
                 directory = argument;
         }

         MainWidget w;
         w.grabGestures(gestures);
         w.show();

         if (directory.isEmpty()) {
             const QString picturesLocation = QDesktopServices::storageLocation(QDesktopServices::PicturesLocation);
             directory =
                 QFileDialog::getExistingDirectory(&w, "Select image folder",
                                                   picturesLocation.isEmpty() ? QString() : picturesLocation);
             if (directory.isEmpty())
                 return 0;
         }

         w.openDirectory(directory);

         return app.exec();
     }