querymainwindow.cpp Example File

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  #include <QMessageBox>
  #include <QFileDialog>
  #include <QtXmlPatterns>

  #include "querymainwindow.h"
  #include "xmlsyntaxhighlighter.h"

  QueryMainWindow::QueryMainWindow() : ui_defaultQueries(0)
  {
      setupUi(this);

      new XmlSyntaxHighlighter(findChild<QTextEdit*>("inputTextEdit")->document());
      new XmlSyntaxHighlighter(findChild<QTextEdit*>("outputTextEdit")->document());

      ui_defaultQueries = findChild<QComboBox*>("defaultQueries");
      QMetaObject::connectSlotsByName(this);
      connect(ui_defaultQueries, SIGNAL(currentIndexChanged(int)), SLOT(displayQuery(int)));

      loadInputFile();
      const QStringList queries(QDir(":/files/", "*.xq").entryList());
      int len = queries.count();
      for(int i = 0; i < len; ++i)
          ui_defaultQueries->addItem(queries.at(i));
      if (len > 0)
          displayQuery(0);
  }

  void QueryMainWindow::displayQuery(int index)
  {
      QFile queryFile(QString(":files/") + ui_defaultQueries->itemText(index));
      queryFile.open(QIODevice::ReadOnly);
      const QString query(QString::fromLatin1(queryFile.readAll()));
      findChild<QTextEdit*>("queryTextEdit")->setPlainText(query);

      evaluate(query);
  }

  void QueryMainWindow::loadInputFile()
  {
      QFile forView;
      forView.setFileName(":/files/cookbook.xml");
      if (!forView.open(QIODevice::ReadOnly)) {
          QMessageBox::information(this,
              tr("Unable to open file"), forView.errorString());
          return;
      }

      QTextStream in(&forView);
      QString inputDocument = in.readAll();
      findChild<QTextEdit*>("inputTextEdit")->setPlainText(inputDocument);
  }

  void QueryMainWindow::evaluate(const QString &str)
  {
      QFile sourceDocument;
      sourceDocument.setFileName(":/files/cookbook.xml");
      sourceDocument.open(QIODevice::ReadOnly);

      QByteArray outArray;
      QBuffer buffer(&outArray);
      buffer.open(QIODevice::ReadWrite);

      QXmlQuery query;
      query.bindVariable("inputDocument", &sourceDocument);
      query.setQuery(str);
      if (!query.isValid())
          return;

      QXmlFormatter formatter(query, &buffer);
      if (!query.evaluateTo(&formatter))
          return;

      buffer.close();
      findChild<QTextEdit*>("outputTextEdit")->setPlainText(QString::fromUtf8(outArray.constData()));

  }