mainwindow.cpp Example File
xmlpatterns/filetree/mainwindow.cpp

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 ** Copyright (C) 2007-2008 Nokia Corporation and/or its subsidiary(-ies). All rights reserved.
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 ** contact qt-sales@nokia.com if any conditions of this licensing
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 #include <QtGui>
 #include <QLibraryInfo>
 #include <QtXmlPatterns>

 #include "mainwindow.h"

 MainWindow::MainWindow() : m_fileTree(m_namePool)
 {
     setupUi(this);

     /* Setup the font. */
     {
         QFont font("Courier",10);
         font.setFixedPitch(true);

         fileTree->setFont(font);
         queryEdit->setFont(font);
         output->setFont(font);
     }

     /* We load one which isn't too big. */
     const QString dir(QLibraryInfo::location(QLibraryInfo::ExamplesPath)  + "/xmlpatterns/filetree");
     qDebug() << dir;

     if(QDir(dir).exists())
         loadDirectory(dir);
     else
         fileTree->setPlainText(tr("Use the Open menu entry to select a directory."));

     const QStringList queries(QDir(":/queries/", "*.xq").entryList());
     int len = queries.count();

     for(int i = 0; i < len; ++i)
         queryBox->addItem(queries.at(i));

 }

 void MainWindow::on_queryBox_currentIndexChanged()
 {
     QFile queryFile(":/queries/" + queryBox->currentText());
     queryFile.open(QIODevice::ReadOnly);

     queryEdit->setPlainText(QString::fromLatin1(queryFile.readAll()));
     evaluateResult();
 }

 void MainWindow::evaluateResult()
 {
     if(queryBox->currentText().isEmpty())
         return;

     QXmlQuery query(m_namePool);
     query.bindVariable("fileTree", m_fileNode);
     query.setQuery(QUrl("qrc:/queries/" + queryBox->currentText()));

     QByteArray formatterOutput;
     QBuffer buffer(&formatterOutput);
     buffer.open(QIODevice::WriteOnly);

     QXmlFormatter formatter(query, &buffer);
     query.evaluateTo(&formatter);

     output->setText(QString::fromLatin1(formatterOutput.constData()));
 }

 void MainWindow::on_actionOpenDirectory_triggered()
 {
     loadDirectory(QFileDialog::getExistingDirectory(this));
 }

 void MainWindow::loadDirectory(const QString &directory)
 {
     Q_ASSERT(QDir(directory).exists());

     m_fileNode = m_fileTree.nodeFor(directory);

     QXmlQuery query(m_namePool);
     query.bindVariable("fileTree", m_fileNode);
     query.setQuery(QUrl("qrc:/queries/wholeTree.xq"));

     QByteArray output;
     QBuffer buffer(&output);
     buffer.open(QIODevice::WriteOnly);

     QXmlFormatter formatter(query, &buffer);
     query.evaluateTo(&formatter);

     treeInfo->setText((QString(tr("%1 rendered as XML.")).arg(directory)));
     fileTree->setText(QString::fromLatin1(output.constData()));
     evaluateResult();
 }

 void MainWindow::on_actionAbout_triggered()
 {
     QMessageBox::about(this, tr("About File Tree"),
                              tr("<p>The <b>File Tree</b> example shows "
                                 "how to use XQuery on top of data of your choice without "
                                 "converting it to an XML document.</p>"
                                 "<p>In this example a QSimpleXmlNodeModel sub-class makes it possible to "
                                 "use the XQuery language's strength of selecting and aggregating on top of "
                                 "the file system.</p>"));
 }