xbelreader.cpp Example File

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    #include "xbelreader.hpp"

    #include <bb/cascades/QmlDocument>

    using namespace bb::cascades;

    XbelReader::XbelReader(Container *treeContainer)
        : m_treeContainer(treeContainer)
    {
    }

    bool XbelReader::read(QIODevice *device)
    {
        // Set the XBEL document as input data to the XML stream reader
        m_xml.setDevice(device);

        // Read the first element ...
        if (m_xml.readNextStartElement()) {
            // ... and check whether this is a valid XBEL file in the correct version
            if (m_xml.name() == "xbel" && m_xml.attributes().value("version") == "1.0")
                readXBEL(); // Start to parse the document
            else
                m_xml.raiseError(QObject::tr("The file is not an XBEL version 1.0 file."));
        }

        return !m_xml.error();
    }

    QString XbelReader::errorString() const
    {
        return QObject::tr("%1\nLine %2, column %3")
                .arg(m_xml.errorString())
                .arg(m_xml.lineNumber())
                .arg(m_xml.columnNumber());
    }

    void XbelReader::readXBEL()
    {
        // Do sanity check
        Q_ASSERT(m_xml.isStartElement() && m_xml.name() == "xbel");

        // Iterate over the child elements
        while (m_xml.readNextStartElement()) {
            if (m_xml.name() == "folder")
                readFolder(m_treeContainer);
            else if (m_xml.name() == "bookmark")
                readBookmark(m_treeContainer);
            else if (m_xml.name() == "separator")
                readSeparator(m_treeContainer);
            else
                m_xml.skipCurrentElement();
        }
    }

    void XbelReader::readTitle(Container *item)
    {
        // Do sanity check
        Q_ASSERT(m_xml.isStartElement() && m_xml.name() == "title");

        // Read the title property and set it on the control
        const QString title = m_xml.readElementText();
        item->setProperty("title", title);
    }

    void XbelReader::readSeparator(Container *item)
    {
        // Do sanity check
        Q_ASSERT(m_xml.isStartElement() && m_xml.name() == "separator");

        // Just create the control, no additional properties are set
        createChildItem(item);
        m_xml.skipCurrentElement();
    }

    void XbelReader::readFolder(Container *item)
    {
        // Do sanity check
        Q_ASSERT(m_xml.isStartElement() && m_xml.name() == "folder");

        // Create the control for the folder ...
        Container *folder = createChildItem(item);

        // ... and iterate over the fild elements
        while (m_xml.readNextStartElement()) {
            if (m_xml.name() == "title")
                readTitle(folder);
            else if (m_xml.name() == "folder")
                readFolder(folder);
            else if (m_xml.name() == "bookmark")
                readBookmark(folder);
            else if (m_xml.name() == "separator")
                readSeparator(folder);
            else
                m_xml.skipCurrentElement();
        }
    }

    void XbelReader::readBookmark(Container *item)
    {
        // Do sanity check
        Q_ASSERT(m_xml.isStartElement() && m_xml.name() == "bookmark");

        // Create the control for the bookmark and set the properties from the element on it
        Container *bookmark = createChildItem(item);
        bookmark->setProperty("title", QObject::tr("Unknown title"));
        bookmark->setProperty("url", m_xml.attributes().value("href").toString());

        // Read the <title> child element
        while (m_xml.readNextStartElement()) {
            if (m_xml.name() == "title")
                readTitle(bookmark);
            else
                m_xml.skipCurrentElement();
        }
    }

    Container *XbelReader::createChildItem(Container *parent)
    {
        const QString tagName = m_xml.name().toString();

        // Use a different QML file depending on the current XBEL element type
        const QString qmlFile = (tagName == "folder" ? "asset:///FolderItem.qml" :
                                 tagName == "bookmark" ? "asset:///BookmarkItem.qml" :
                                 tagName == "separator" ? "asset:///SeparatorItem.qml" : QString());

        Container *container = 0;

        // Load the QML file ...
        QmlDocument *qml = QmlDocument::create(qmlFile);
        if (!qml->hasErrors()) {
            // ... create the top-level control ...
            container = qml->createRootObject<Container>();

            // ... and add it to the parent container
            parent->add(container);
        }

        return container;
    }