Android中关于Audio库的知识

Android会自动扫描外存（SD卡）中的文件，获取到audio类型的文件，分析文件后，将信息数据存储在 MediaStore.Audio.AudioColumns表内，该表的结构如下：

字段包括如下：

Constants
String	ALBUM	The album the audio file is from, if any Type: TEXT
String	ALBUM_ID	The id of the album the audio file is from, if any Type: INTEGER (long)
String	ALBUM_KEY	A non human readable key calculated from the ALBUM, used for searching, sorting and grouping Type: TEXT
String	ARTIST	The artist who created the audio file, if any Type: TEXT
String	ARTIST_ID	The id of the artist who created the audio file, if any Type: INTEGER (long)
String	ARTIST_KEY	A non human readable key calculated from the ARTIST, used for searching, sorting and grouping Type: TEXT
String	BOOKMARK	The position, in ms, playback was at when playback for this file was last stopped.
String	COMPOSER	The composer of the audio file, if any Type: TEXT
String	DURATION	The duration of the audio file, in ms Type: INTEGER (long)
String	IS_ALARM	Non-zero if the audio file may be an alarm Type: INTEGER (boolean)
String	IS_MUSIC	Non-zero if the audio file is music Type: INTEGER (boolean)
String	IS_NOTIFICATION	Non-zero if the audio file may be a notification sound Type: INTEGER (boolean)
String	IS_PODCAST	Non-zero if the audio file is a podcast Type: INTEGER (boolean)
String	IS_RINGTONE	Non-zero if the audio file may be a ringtone Type: INTEGER (boolean)
String	TITLE_KEY	A non human readable key calculated from the TITLE, used for searching, sorting and grouping Type: TEXT
String	TRACK	The track number of this song on the album, if any.
String	YEAR	The year the audio file was recorded, if any Type: INTEGER

[Collapse] Inherited Constants
From interfaceandroid.provider.BaseColumns String _COUNT The count of rows in a directory. String _ID The unique ID for a row.
From interfaceandroid.provider.MediaStore.MediaColumns String DATA The data stream for the file Type: DATA STREAM String DATE_ADDED The time the file was added to the media provider Units are seconds since 1970. String DATE_MODIFIED The time the file was last modified Units are seconds since 1970. String DISPLAY_NAME The display name of the file Type: TEXT String MIME_TYPE The MIME type of the file Type: TEXT String SIZE The size of the file in bytes Type: INTEGER (long) String TITLE The title of the content Type: TEXT

类MediaStore.Audio.Media

描述了手机内和SD卡Audio文件的URI

Fields
public static final Uri	EXTERNAL_CONTENT_URI	The content:// style URI for the "primary" external storage volume.
public static final Uri	INTERNAL_CONTENT_URI	The content:// style URI for the internal storage.