File path=getExternalFilesDir(type);
type可以為:
null，//根目錄
Environment.DIRECTORY_MUSIC //創(chuàng)建一個music目錄
Environment.DIRECTORY_PODCASTS //創(chuàng)建一個podcasts目錄
Environment.DIRECTORY_RINGTONES //創(chuàng)建一個ringtones目錄
Environment.DIRECTORY_ALARMS //創(chuàng)建一個alarms目錄
Environment.DIRECTORY_NOTIFICATIONS //創(chuàng)建一個notifications目錄
Environment.DIRECTORY_PICTURES //創(chuàng)建一個pictures目錄
Environment#DIRECTORY_MOVIES //創(chuàng)建一個movies目錄
