src/engineobserver.cpp

   1 /***************************************************************************
   2                       engineobserver.cpp  -  Observer pattern for engine
   3                          -------------------
   4 begin                : Mar 14 2003
   5 copyright            : (C) 2003 by Frederik Holljen
   6 email                : fh@ez.no
   7 ***************************************************************************/
   8
   9 /***************************************************************************
  10  *                                                                         *
  11  *   This program is free software; you can redistribute it and/or modify  *
  12  *   it under the terms of the GNU General Public License as published by  *
  13  *   the Free Software Foundation; either version 2 of the License, or     *
  14  *   (at your option) any later version.                                   *
  15  *                                                                         *
  16  ***************************************************************************/
  17
  18 #include "engineobserver.h"
  19
  20 #include "debug.h"
  21 #include "collectiondb.h"
  22 #include "podcastbundle.h"
  23
  24
  25 //////////////////////////////////////////////////////////////////////////////////////////
  26 /// CLASS EngineObserver
  27 //////////////////////////////////////////////////////////////////////////////////////////
  28
  29 EngineObserver::EngineObserver()
  30     : m_subject( 0 )
  31 {}
  32
  33 EngineObserver::EngineObserver( EngineSubject *s )
  34     : m_subject( s )
  35 {
  36    m_subject->attach( this );
  37 }
  38
  39 EngineObserver::~EngineObserver()
  40 {
  41     if ( m_subject )
  42         m_subject->detach( this );
  43 }
  44
  45 void
  46 EngineObserver::engineStateChanged( Engine::State currentState, Engine::State oldState )
  47 {
  48     Q_UNUSED( oldState );
  49     Q_UNUSED( currentState );
  50 }
  51
  52 void
  53 EngineObserver::engineTrackEnded( int finalPosition, int trackLength, const QString &reason )
  54 {
  55     Q_UNUSED( finalPosition );
  56     Q_UNUSED( trackLength );
  57     Q_UNUSED( reason );
  58 }
  59
  60 void
  61 EngineObserver::engineNewTrackPlaying()
  62 {
  63 }
  64
  65 void
  66 EngineObserver::engineNewMetaData( const QHash<qint64, QString> &newMetaData, bool trackChanged )
  67 {
  68     Q_UNUSED( newMetaData );
  69     Q_UNUSED( trackChanged );
  70 }
  71
  72 void
  73 EngineObserver::engineVolumeChanged( int percent )
  74 {
  75     Q_UNUSED( percent );
  76 }
  77
  78 void
  79 EngineObserver::engineTrackPositionChanged( long position , bool userSeek )
  80 {
  81     Q_UNUSED( position );
  82     Q_UNUSED( userSeek );
  83 }
  84
  85 void
  86 EngineObserver::engineTrackLengthChanged( long seconds )
  87 {
  88     Q_UNUSED( seconds );
  89 }
  90
  91 //////////////////////////////////////////////////////////////////////////////////////////
  92 /// CLASS EngineSubject
  93 //////////////////////////////////////////////////////////////////////////////////////////
  94
  95 EngineSubject::EngineSubject()
  96     : m_oldEngineState( Engine::Empty )
  97 {}
  98
  99 EngineSubject::~EngineSubject()
 100 {
 101     //do not delete the observers, we don't ahve ownership of them!
 102 }
 103
 104
 105 void EngineSubject::stateChangedNotify( Engine::State state )
 106 {
 107     foreach( EngineObserver *observer, Observers )
 108     {
 109         observer->engineStateChanged( state, m_oldEngineState );
 110     }
 111
 112     m_oldEngineState = state;
 113 }
 114
 115 void EngineSubject::trackEnded( int finalPosition, int trackLength, const QString &reason )
 116 {
 117     foreach( EngineObserver *observer, Observers )
 118         observer->engineTrackEnded( finalPosition, trackLength, reason );
 119 }
 120
 121 void
 122 EngineSubject::newMetaDataNotify( const QHash<qint64, QString> &newMetaData, bool trackChanged ) const
 123 {
 124     foreach( EngineObserver *observer, Observers )
 125         observer->engineNewMetaData( newMetaData, trackChanged );
 126 }
 127
 128 void EngineSubject::volumeChangedNotify( int percent )
 129 {
 130     foreach( EngineObserver *observer, Observers )
 131     {
 132         observer->engineVolumeChanged( percent );
 133     }
 134 }
 135
 136
 137 void EngineSubject::trackPositionChangedNotify( long position, bool userSeek )
 138 {
 139     foreach( EngineObserver *observer, Observers )
 140     {
 141         observer->engineTrackPositionChanged( position, userSeek );
 142     }
 143 }
 144
 145
 146 void EngineSubject::trackLengthChangedNotify( long seconds )
 147 {
 148     foreach( EngineObserver *observer, Observers )
 149     {
 150         observer->engineTrackLengthChanged( seconds );
 151     }
 152 }
 153
 154 void
 155 EngineSubject::newTrackPlaying() const
 156 {
 157     foreach( EngineObserver *observer, Observers )
 158         observer->engineNewTrackPlaying();
 159 }
 160
 161
 162 void EngineSubject::attach( EngineObserver *observer )
 163 {
 164     if( !observer )
 165         return;
 166     Observers.insert( observer );
 167 }
 168
 169
 170 void EngineSubject::detach( EngineObserver *observer )
 171 {
 172     Observers.remove( observer );
 173 }