Android Environment 常量含义

String MEDIA_BAD_REMOVAL Storage state if the media was removed before it was unmounted.
String MEDIA_CHECKING         Storage state if the media is present and being disk-checked.
String MEDIA_EJECTING Storage state if the media is in the process of being ejected.
String MEDIA_MOUNTED Storage state if the media is present and mounted at its mount point with read/write access.
String MEDIA_MOUNTED_READ_ONLY Storage state if the media is present and mounted at its mount point with read-only access.
String MEDIA_NOFS Storage state if the media is present but is blank or is using an unsupported filesystem.
String MEDIA_REMOVED Storage state if the media is not present.
String MEDIA_SHARED Storage state if the media is present not mounted, and shared via USB mass storage.
String MEDIA_UNKNOWN Unknown storage state, such as when a path isn't backed by known storage media.
String MEDIA_UNMOUNTABLE Storage state if the media is present but cannot be mounted.

String MEDIA_UNMOUNTED Storage state if the media is present but not mounted.

public static String DIRECTORY_ALARMS Standard directory in which to place any audio files that should be in the list of alarms that the user can select (not as regular music).
public static String DIRECTORY_DCIM The traditional location for pictures and videos when mounting the device as a camera.
public static String DIRECTORY_DOCUMENTS Standard directory in which to place documents that have been created by the user.
public static String DIRECTORY_DOWNLOADS Standard directory in which to place files that have been downloaded by the user.
public static String DIRECTORY_MOVIES Standard directory in which to place movies that are available to the user.
public static String DIRECTORY_MUSIC Standard directory in which to place any audio files that should be in the regular list of music for the user.
public static String DIRECTORY_NOTIFICATIONS Standard directory in which to place any audio files that should be in the list of notifications that the user can select (not as regular music).
public static String DIRECTORY_PICTURES Standard directory in which to place pictures that are available to the user.
public static String DIRECTORY_PODCASTS Standard directory in which to place any audio files that should be in the list of podcasts that the user can select (not as regular music).
public static String DIRECTORY_RINGTONES Standard directory in which to place any audio files that should be in the list of ringtones that the user can select (not as regular music).