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# mainwindow.cpp Example File

painting/svgviewer/mainwindow.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.
     **   * Neither the name of The Qt Company Ltd 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."
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     ****************************************************************************/

     #include "mainwindow.h"

     #include <QtGui>

     #include "svgview.h"

     MainWindow::MainWindow()
         : QMainWindow()
         , m_view(new SvgView)
     {
         QMenu *fileMenu = new QMenu(tr("&File"), this);
         QAction *openAction = fileMenu->addAction(tr("&Open..."));
         openAction->setShortcut(QKeySequence(tr("Ctrl+O")));
         QAction *quitAction = fileMenu->addAction(tr("E&xit"));
         quitAction->setShortcuts(QKeySequence::Quit);

         menuBar()->addMenu(fileMenu);

         QMenu *viewMenu = new QMenu(tr("&View"), this);
         m_backgroundAction = viewMenu->addAction(tr("&Background"));
         m_backgroundAction->setEnabled(false);
         m_backgroundAction->setCheckable(true);
         m_backgroundAction->setChecked(false);
         connect(m_backgroundAction, SIGNAL(toggled(bool)), m_view, SLOT(setViewBackground(bool)));

         m_outlineAction = viewMenu->addAction(tr("&Outline"));
         m_outlineAction->setEnabled(false);
         m_outlineAction->setCheckable(true);
         m_outlineAction->setChecked(true);
         connect(m_outlineAction, SIGNAL(toggled(bool)), m_view, SLOT(setViewOutline(bool)));

         menuBar()->addMenu(viewMenu);

         QMenu *rendererMenu = new QMenu(tr("&Renderer"), this);
         m_nativeAction = rendererMenu->addAction(tr("&Native"));
         m_nativeAction->setCheckable(true);
         m_nativeAction->setChecked(true);
     #ifndef QT_NO_OPENGL
         m_glAction = rendererMenu->addAction(tr("&OpenGL"));
         m_glAction->setCheckable(true);
     #endif
         m_imageAction = rendererMenu->addAction(tr("&Image"));
         m_imageAction->setCheckable(true);

     #ifndef QT_NO_OPENGL
         rendererMenu->addSeparator();
         m_highQualityAntialiasingAction = rendererMenu->addAction(tr("&High Quality Antialiasing"));
         m_highQualityAntialiasingAction->setEnabled(false);
         m_highQualityAntialiasingAction->setCheckable(true);
         m_highQualityAntialiasingAction->setChecked(false);
         connect(m_highQualityAntialiasingAction, SIGNAL(toggled(bool)), m_view, SLOT(setHighQualityAntialiasing(bool)));
     #endif

         QActionGroup *rendererGroup = new QActionGroup(this);
         rendererGroup->addAction(m_nativeAction);
     #ifndef QT_NO_OPENGL
         rendererGroup->addAction(m_glAction);
     #endif
         rendererGroup->addAction(m_imageAction);

         menuBar()->addMenu(rendererMenu);

         connect(openAction, SIGNAL(triggered()), this, SLOT(openFile()));
         connect(quitAction, SIGNAL(triggered()), qApp, SLOT(quit()));
         connect(rendererGroup, SIGNAL(triggered(QAction*)),
                 this, SLOT(setRenderer(QAction*)));

         setCentralWidget(m_view);
         setWindowTitle(tr("SVG Viewer"));
     }

     void MainWindow::openFile(const QString &path)
     {
         QString fileName;
         if (path.isNull())
             fileName = QFileDialog::getOpenFileName(this, tr("Open SVG File"),
                     m_currentPath, "SVG files (*.svg *.svgz *.svg.gz)");
         else
             fileName = path;

         if (!fileName.isEmpty()) {
             QFile file(fileName);
             if (!file.exists()) {
                 QMessageBox::critical(this, tr("Open SVG File"),
                                QString("Could not open file '%1'.").arg(fileName));

                 m_outlineAction->setEnabled(false);
                 m_backgroundAction->setEnabled(false);
                 return;
             }

             m_view->openFile(file);

             if (!fileName.startsWith(":/")) {
                 m_currentPath = fileName;
                 setWindowTitle(tr("%1 - SVGViewer").arg(m_currentPath));
             }

             m_outlineAction->setEnabled(true);
             m_backgroundAction->setEnabled(true);

             resize(m_view->sizeHint() + QSize(80, 80 + menuBar()->height()));
         }
     }

     void MainWindow::setRenderer(QAction *action)
     {
     #ifndef QT_NO_OPENGL
         m_highQualityAntialiasingAction->setEnabled(false);
     #endif

         if (action == m_nativeAction)
             m_view->setRenderer(SvgView::Native);
     #ifndef QT_NO_OPENGL
         else if (action == m_glAction) {
             m_highQualityAntialiasingAction->setEnabled(true);
             m_view->setRenderer(SvgView::OpenGL);
         }
     #endif
         else if (action == m_imageAction) {
             m_view->setRenderer(SvgView::Image);
         }
     }