声明在 android/ijkplayer/ijkplayer-java/src/main/java/tv/danmaku/ijk/media/player/IjkMediaPlayer.java 中：
private static final int MEDIA_NOP = 0; // interface test message
private static final int MEDIA_PREPARED = 1;
private static final int MEDIA_PLAYBACK_COMPLETE = 2;
private static final int MEDIA_BUFFERING_UPDATE = 3;
private static final int MEDIA_SEEK_COMPLETE = 4;
private static final int MEDIA_SET_VIDEO_SIZE = 5;
private static final int MEDIA_TIMED_TEXT = 99;
private static final int MEDIA_ERROR = 100;
private static final int MEDIA_INFO = 200;