Android查询系统的音频（音乐播放器的核心）

 1 //查询系统的音频库
 2     public static List<MusicBean> getMusicInfo(Context context){
 3         List<MusicBean> musicList= new ArrayList<>();
 4         //查询音频数据库
 5         Cursor c = context.getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, null, MediaStore.Audio.Media.DURATION+">=?", new String[]{"20000"}, MediaStore.Audio.Media.DEFAULT_SORT_ORDER);
 6 
 7         while (c.moveToNext()){
 8            MusicBean musicBean=new MusicBean();
 9             musicBean.setTitle(c.getString(c.getColumnIndex(MediaStore.Audio.Media.TITLE)));
10             musicBean.setName(c.getString(c.getColumnIndex(MediaStore.Audio.Media.DISPLAY_NAME)));
11             //对未知艺术家进行判断
12             String singer = c.getString(c.getColumnIndex(MediaStore.Audio.Media.ARTIST));
13             if(singer==null || "".equals(singer) || "<unknown>".equals(singer)){
14                 singer = "未知艺术家";
15             }
16             musicBean.setSinger(singer);
17             musicBean.setAlbum(c.getString(c.getColumnIndex(MediaStore.Audio.Media.ALBUM)));
18             musicBean.setSize(c.getLong(c.getColumnIndex(MediaStore.Audio.Media.SIZE)));
19             musicBean.setTime(c.getLong(c.getColumnIndex(MediaStore.Audio.Media.DURATION)));
20             musicBean.setUrl(c.getString(c.getColumnIndex(MediaStore.Audio.Media.DATA)));
21             musicList.add(musicBean);
22 
23         }
24         //关闭游标，释放资源
25         c.close();
26         return musicList;
27     }