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# mainwindow.cpp Example File

xmlpatterns/qobjectxmlmodel/mainwindow.cpp

     /****************************************************************************
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     ** This file is part of the examples of the Qt Toolkit.
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     #include <QtGui>
     #include <QtXmlPatterns>

     #include "mainwindow.h"
     #include "qobjectxmlmodel.h"
     #include "xmlsyntaxhighlighter.h"

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

         new XmlSyntaxHighlighter(wholeTreeOutput->document());

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

             wholeTree->setFont(font);
             wholeTreeOutput->setFont(font);
             htmlQueryEdit->setFont(font);
         }

         QXmlNamePool namePool;
         QObjectXmlModel qObjectModel(this, namePool);
         QXmlQuery query(namePool);

         /* The QObject tree as XML view. */
         {
             query.bindVariable("root", qObjectModel.root());
             query.setQuery(QUrl("qrc:/queries/wholeTree.xq"));

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

             /* Let's the use the formatter, so it's a bit easier to read. */
             QXmlFormatter serializer(query, &buffer);

             query.evaluateTo(&serializer);
             buffer.close();

             {
                 QFile queryFile(":/queries/wholeTree.xq");
                 queryFile.open(QIODevice::ReadOnly);
                 wholeTree->setPlainText(QString::fromUtf8(queryFile.readAll()));
                 wholeTreeOutput->setPlainText(QString::fromUtf8(output.constData()));
             }
         }

         /* The QObject occurrence statistics as HTML view. */
         {
             query.setQuery(QUrl("qrc:/queries/statisticsInHTML.xq"));
             Q_ASSERT(query.isValid());

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

             /* Let's the use the serializer, so we gain a bit of speed. */
             QXmlSerializer serializer(query, &buffer);

             query.evaluateTo(&serializer);
             buffer.close();

             {
                 QFile queryFile(":/queries/statisticsInHTML.xq");
                 queryFile.open(QIODevice::ReadOnly);
                 htmlQueryEdit->setPlainText(QString::fromUtf8(queryFile.readAll()));
                 htmlOutput->setHtml(QString(output));
             }
         }
     }

     void MainWindow::on_actionAbout_triggered()
     {
         QMessageBox::about(this,
                            tr("About QObject XML Model"),
                            tr("<p>The <b>QObject XML Model</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 subclass "
                               "makes it possible to query a QObject tree using "
                               "XQuery and retrieve the result as pointers to "
                               "QObjects, or as XML.</p>"
                               "<p>A possible use case of this could be to write "
                               "an application that tests a graphical interface "
                               "against Human Interface Guidelines, or that "
                               "queries an application's data which is modeled "
                               "using a QObject tree and dynamic properties."));
     }