thanks to tip !

I did little modifications to my code :
Qt Code: 
  1. while (!m_xml.atEnd()) {
  2.         m_xml.readNext();
  3.         if (m_xml.isStartElement()) {
  4.             m_currentTag = m_xml.name().toString();
  5.             qDebug () << "start "  <<  m_currentTag;
  6.             if (m_xml.name() == "enclosure" && newFeeds)   {
  7.                 feedItem.m_enclosure.m_url =  m_xml.attributes().value("url").toString();
  8.                 feedItem.m_enclosure.m_type = m_xml.attributes().value("type").toString();
  9.             }
  10.         } else if (m_xml.isEndElement()) {
  11.             if (m_xml.name() == "item") {
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This solved my problem. This may be not efficient but now I can parse the enclosure element.