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# mainwindow.cpp Example File

xml/saxbookmarks/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.
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     **
     ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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     #include <QtGui>

     #include "mainwindow.h"
     #include "xbelgenerator.h"
     #include "xbelhandler.h"

     MainWindow::MainWindow()
     {
         QStringList labels;
         labels << tr("Title") << tr("Location");

         treeWidget = new QTreeWidget;
         treeWidget->header()->setResizeMode(QHeaderView::Stretch);
         treeWidget->setHeaderLabels(labels);
         setCentralWidget(treeWidget);

         createActions();
         createMenus();

         statusBar()->showMessage(tr("Ready"));

         setWindowTitle(tr("SAX Bookmarks"));
         resize(480, 320);
     }

     void MainWindow::open()
     {
     #if defined(Q_OS_SYMBIAN)
         // Look for bookmarks on the same drive where the application is installed to,
         // if drive is not read only. QDesktopServices::DataLocation does this check,
         // and returns writable drive.
         QString bookmarksFolder =
                 QDesktopServices::storageLocation(QDesktopServices::DataLocation).left(1);
         bookmarksFolder.append(":/Data/qt/saxbookmarks");
         QDir::setCurrent(bookmarksFolder);
     #endif
         QString fileName =
                 QFileDialog::getOpenFileName(this, tr("Open Bookmark File"),
                                              QDir::currentPath(),
                                              tr("XBEL Files (*.xbel *.xml)"));
         if (fileName.isEmpty())
             return;

         treeWidget->clear();

         XbelHandler handler(treeWidget);
         QXmlSimpleReader reader;
         reader.setContentHandler(&handler);
         reader.setErrorHandler(&handler);

         QFile file(fileName);
         if (!file.open(QFile::ReadOnly | QFile::Text)) {
             QMessageBox::warning(this, tr("SAX Bookmarks"),
                                  tr("Cannot read file %1:\n%2.")
                                  .arg(fileName)
                                  .arg(file.errorString()));
             return;
         }

         QXmlInputSource xmlInputSource(&file);
         if (reader.parse(xmlInputSource))
             statusBar()->showMessage(tr("File loaded"), 2000);
     }

     void MainWindow::saveAs()
     {
         QString fileName =
                 QFileDialog::getSaveFileName(this, tr("Save Bookmark File"),
                                              QDir::currentPath(),
                                              tr("XBEL Files (*.xbel *.xml)"));
         if (fileName.isEmpty())
             return;

         QFile file(fileName);
         if (!file.open(QFile::WriteOnly | QFile::Text)) {
             QMessageBox::warning(this, tr("SAX Bookmarks"),
                                  tr("Cannot write file %1:\n%2.")
                                  .arg(fileName)
                                  .arg(file.errorString()));
             return;
         }

         XbelGenerator generator(treeWidget);
         if (generator.write(&file))
             statusBar()->showMessage(tr("File saved"), 2000);
     }

     void MainWindow::about()
     {
        QMessageBox::about(this, tr("About SAX Bookmarks"),
                 tr("The <b>SAX Bookmarks</b> example demonstrates how to use Qt's "
                    "SAX classes to read XML documents and how to generate XML by "
                    "hand."));
     }

     void MainWindow::createActions()
     {
         openAct = new QAction(tr("&Open..."), this);
         openAct->setShortcuts(QKeySequence::Open);
         connect(openAct, SIGNAL(triggered()), this, SLOT(open()));

         saveAsAct = new QAction(tr("&Save As..."), this);
         saveAsAct->setShortcuts(QKeySequence::SaveAs);
         connect(saveAsAct, SIGNAL(triggered()), this, SLOT(saveAs()));

         exitAct = new QAction(tr("E&xit"), this);
         exitAct->setShortcuts(QKeySequence::Quit);
         connect(exitAct, SIGNAL(triggered()), this, SLOT(close()));

         aboutAct = new QAction(tr("&About"), this);
         connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));

         aboutQtAct = new QAction(tr("About &Qt"), this);
         connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));
     }

     void MainWindow::createMenus()
     {
         fileMenu = menuBar()->addMenu(tr("&File"));
         fileMenu->addAction(openAct);
         fileMenu->addAction(saveAsAct);
         fileMenu->addAction(exitAct);

         menuBar()->addSeparator();

         helpMenu = menuBar()->addMenu(tr("&Help"));
         helpMenu->addAction(aboutAct);
         helpMenu->addAction(aboutQtAct);
     }