querymainwindow.cpp Example File

recipes/querymainwindow.cpp
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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()));

}

© 2016 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.