kget/core/plugin/plugin.h

   1 /* This file is part of the KDE project
   2
   3    Copyright (C) 2005 by Enrico Ros <eros.kde@email.it>
   4    based on amarok code Copyright (C) 2004 by Mark Kretschmann <markey@web.de>
   5
   6    This program is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU General Public
   8    License as published by the Free Software Foundation; either
   9    version 2 of the License, or (at your option) any later version.
  10 */
  11
  12 #ifndef KGET_PLUGIN_H
  13 #define KGET_PLUGIN_H
  14
  15 /* KGet plugins -How they work- [enrico: 0.6]
  16  *
  17  * Here is a generic framework for plugins usage. Since the purpose of a
  18  * plugin is providing some type of well known functionality, there are
  19  * some requirements that must be satisfied. In fact a plugin must:
  20  * - inherit KGetPlugin interface or a subclass of that
  21  * - declare that the class IS a kget plugin (using a macro)
  22  * - declare its 'type' to the loader (using a .desktop file)
  23  *
  24  * Plugins providing the same functionality (TransferFactory for example)
  25  * must inherit the same interface and be declared as plugins of the same
  26  * type. In that case all the plugins will inherit and implement the
  27  * TransferFactory class and provide a .desktop file that identify them
  28  * as belonging to the same type (X-KDE-KGet-pluginType=TransferFactory).
  29  *
  30  * Loading. This operation is done by using KDE framework. So we define a
  31  * new ServiceType in the kget_plugin.desktop file. KGet plugins service
  32  * is called "KGet/Plugin". In the Desktop file that describes a plugin
  33  * the "X-KDE-ServiceType" is set to to "KGet/Plugin" and other fields
  34  * are set as described in the service type definition.
  35  * As an example say that we need "InputFilter" plugins. In that case we
  36  * can use KTrader to enumerate the plugins of that type installed in the
  37  * system and after getting the name of the libraries they're in, load
  38  * them. In that case the Input object that loaded the plugins must know
  39  * how to treat them (and that is easy, since they all reimplemented an
  40  * 'input plugin class' providing necessary information).
  41  *
  42  * @see: kget_plugin.desktop - for servicetype definition.
  43  * @see: other headers in the dir - for plugin types definition.
  44  */
  45
  46 #include "kget_export.h"
  47
  48 /**
  49  * Bump this number whenever the plugin framework gets
  50  * incompatible with older versions
  51  */
  52  const int FrameworkVersion = 1;
  53
  54 /**
  55  * @short Base class for kget plugins.
  56  * ...
  57  */
  58 class KGET_EXPORT KGetPlugin
  59 {
  60     public:
  61         KGetPlugin();
  62         virtual ~KGetPlugin();
  63
  64         /*
  65         // set and retrieve properties
  66         void addPluginProperty( const QString & key, const QString & value );
  67         bool hasPluginProperty( const QString & key );
  68         QString pluginProperty( const QString & key );
  69
  70          reimplement this to set the type of the plugin
  71         enum PluginType { PreProcessing, Factory, PostProcessing }
  72         virtual PluginType pluginType() = 0;
  73         */
  74
  75     private:
  76         //QMap< QString, QString > m_properties;
  77
  78
  79 };
  80
  81 #endif