text: 
  #pragma once
  
  #include<SFML/Audio.hpp>
  
  class SFMLMusic : public Music
  {
  public:
  	SFMLMusic();
      SFMLMusic(int id, const char *filename);
  	virtual ~SFMLMusic();
  
      int load(int id, const char *filename);
  
  	// sound
  	void play();
  	void loop();
  	void stop();
  
  	bool isPlaying();
      void fade(float targetVolume, float ms_seconds){/* TODO:*/};
  	void free();
  	void updateStatus();
  
  	int getID();
  	virtual const char* getSource();
  
      // sample
      void setVolume(float volume);
      float getVolume();
  
  private:
  	int init();
  
  	int		iID;
  	const char  *szFilename;
  	float fVolume;
      sf::Music music;
  };
  