xbel.cpp Example File

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  #include "xbel.h"

  #include <QtCore/QFile>

  BookmarkNode::BookmarkNode(BookmarkNode::Type type, BookmarkNode *parent) :
       expanded(false)
     , m_parent(parent)
     , m_type(type)
  {
      if (parent)
          parent->add(this);
  }

  BookmarkNode::~BookmarkNode()
  {
      if (m_parent)
          m_parent->remove(this);
      qDeleteAll(m_children);
      m_parent = 0;
      m_type = BookmarkNode::Root;
  }

  bool BookmarkNode::operator==(const BookmarkNode &other)
  {
      if (url != other.url
          || title != other.title
          || desc != other.desc
          || expanded != other.expanded
          || m_type != other.m_type
          || m_children.count() != other.m_children.count())
          return false;

      for (int i = 0; i < m_children.count(); ++i)
          if (!((*(m_children[i])) == (*(other.m_children[i]))))
              return false;
      return true;
  }

  BookmarkNode::Type BookmarkNode::type() const
  {
      return m_type;
  }

  void BookmarkNode::setType(Type type)
  {
      m_type = type;
  }

  QList<BookmarkNode *> BookmarkNode::children() const
  {
      return m_children;
  }

  BookmarkNode *BookmarkNode::parent() const
  {
      return m_parent;
  }

  void BookmarkNode::add(BookmarkNode *child, int offset)
  {
      Q_ASSERT(child->m_type != Root);
      if (child->m_parent)
          child->m_parent->remove(child);
      child->m_parent = this;
      if (-1 == offset)
          offset = m_children.size();
      m_children.insert(offset, child);
  }

  void BookmarkNode::remove(BookmarkNode *child)
  {
      child->m_parent = 0;
      m_children.removeAll(child);
  }

  XbelReader::XbelReader()
  {
  }

  BookmarkNode *XbelReader::read(const QString &fileName)
  {
      QFile file(fileName);
      if (!file.exists()) {
          return new BookmarkNode(BookmarkNode::Root);
      }
      file.open(QFile::ReadOnly);
      return read(&file);
  }

  BookmarkNode *XbelReader::read(QIODevice *device)
  {
      BookmarkNode *root = new BookmarkNode(BookmarkNode::Root);
      setDevice(device);
      if (readNextStartElement()) {
          QString version = attributes().value(QLatin1String("version")).toString();
          if (name() == QLatin1String("xbel")
              && (version.isEmpty() || version == QLatin1String("1.0"))) {
              readXBEL(root);
          } else {
              raiseError(QObject::tr("The file is not an XBEL version 1.0 file."));
          }
      }
      return root;
  }

  void XbelReader::readXBEL(BookmarkNode *parent)
  {
      Q_ASSERT(isStartElement() && name() == QLatin1String("xbel"));

      while (readNextStartElement()) {
          if (name() == QLatin1String("folder"))
              readFolder(parent);
          else if (name() == QLatin1String("bookmark"))
              readBookmarkNode(parent);
          else if (name() == QLatin1String("separator"))
              readSeparator(parent);
          else
              skipCurrentElement();
      }
  }

  void XbelReader::readFolder(BookmarkNode *parent)
  {
      Q_ASSERT(isStartElement() && name() == QLatin1String("folder"));

      BookmarkNode *folder = new BookmarkNode(BookmarkNode::Folder, parent);
      folder->expanded = (attributes().value(QLatin1String("folded")) == QLatin1String("no"));

      while (readNextStartElement()) {
          if (name() == QLatin1String("title"))
              readTitle(folder);
          else if (name() == QLatin1String("desc"))
              readDescription(folder);
          else if (name() == QLatin1String("folder"))
              readFolder(folder);
          else if (name() == QLatin1String("bookmark"))
              readBookmarkNode(folder);
          else if (name() == QLatin1String("separator"))
              readSeparator(folder);
          else
              skipCurrentElement();
      }
  }

  void XbelReader::readTitle(BookmarkNode *parent)
  {
      Q_ASSERT(isStartElement() && name() == QLatin1String("title"));
      parent->title = readElementText();
  }

  void XbelReader::readDescription(BookmarkNode *parent)
  {
      Q_ASSERT(isStartElement() && name() == QLatin1String("desc"));
      parent->desc = readElementText();
  }

  void XbelReader::readSeparator(BookmarkNode *parent)
  {
      new BookmarkNode(BookmarkNode::Separator, parent);
      // empty elements have a start and end element
      readNext();
  }

  void XbelReader::readBookmarkNode(BookmarkNode *parent)
  {
      Q_ASSERT(isStartElement() && name() == QLatin1String("bookmark"));
      BookmarkNode *bookmark = new BookmarkNode(BookmarkNode::Bookmark, parent);
      bookmark->url = attributes().value(QLatin1String("href")).toString();
      while (readNextStartElement()) {
          if (name() == QLatin1String("title"))
              readTitle(bookmark);
          else if (name() == QLatin1String("desc"))
              readDescription(bookmark);
          else
              skipCurrentElement();
      }
      if (bookmark->title.isEmpty())
          bookmark->title = QObject::tr("Unknown title");
  }

  XbelWriter::XbelWriter()
  {
      setAutoFormatting(true);
  }

  bool XbelWriter::write(const QString &fileName, const BookmarkNode *root)
  {
      QFile file(fileName);
      if (!root || !file.open(QFile::WriteOnly))
          return false;
      return write(&file, root);
  }

  bool XbelWriter::write(QIODevice *device, const BookmarkNode *root)
  {
      setDevice(device);

      writeStartDocument();
      writeDTD(QLatin1String("<!DOCTYPE xbel>"));
      writeStartElement(QLatin1String("xbel"));
      writeAttribute(QLatin1String("version"), QLatin1String("1.0"));
      if (root->type() == BookmarkNode::Root) {
          for (int i = 0; i < root->children().count(); ++i)
              writeItem(root->children().at(i));
      } else {
          writeItem(root);
      }

      writeEndDocument();
      return true;
  }

  void XbelWriter::writeItem(const BookmarkNode *parent)
  {
      switch (parent->type()) {
      case BookmarkNode::Folder:
          writeStartElement(QLatin1String("folder"));
          writeAttribute(QLatin1String("folded"), parent->expanded ? QLatin1String("no") : QLatin1String("yes"));
          writeTextElement(QLatin1String("title"), parent->title);
          for (int i = 0; i < parent->children().count(); ++i)
              writeItem(parent->children().at(i));
          writeEndElement();
          break;
      case BookmarkNode::Bookmark:
          writeStartElement(QLatin1String("bookmark"));
          if (!parent->url.isEmpty())
              writeAttribute(QLatin1String("href"), parent->url);
          writeTextElement(QLatin1String("title"), parent->title);
          if (!parent->desc.isEmpty())
              writeAttribute(QLatin1String("desc"), parent->desc);
          writeEndElement();
          break;
      case BookmarkNode::Separator:
          writeEmptyElement(QLatin1String("separator"));
          break;
      default:
          break;
      }
  }