annotate base/XmlExportable.h @ 335:02d2ad95ea52 spectrogram-cache-rejig

* Get storage advice for each cache in an FFT data server.  Allows us to be
  more confident about the actual memory situation and cut over from memory
  to disc part way through an FFT calculation if necessary.  StorageAdviser
  is now a bit too optimistic though (it's too keen to allocate large numbers
  of small blocks in memory).

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2006 Chris Cannam.
    
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

#ifndef _XML_EXPORTABLE_H_
#define _XML_EXPORTABLE_H_

#include <QString>
#include <QColor>

class QTextStream;

class XmlExportable
{
public:
    virtual ~XmlExportable() { }

    /**
     * Stream this exportable object out to XML on a text stream.
     */
    virtual void toXml(QTextStream &stream,
                       QString indent = "",
                       QString extraAttributes = "") const = 0;

    /**
     * Convert this exportable object to XML in a string.  The default
     * implementation calls toXml and returns the result as a string.
     * Do not override this unless you really know what you're doing.
     */
    virtual QString toXmlString(QString indent = "",
				QString extraAttributes = "") const;

    static QString encodeEntities(QString);

    static QString encodeColour(QColor); 

    static int getObjectExportId(const void *); // thread-safe
};

#endif