question: private boolean checkExternalStorageAndNotify ( String filename , String fullDirPath , String externalStorageStatus ) { if ( fullDirPath == null ) { Log . e ( TAG , "Download failed: no SD card" ) ; alertDownloadFailure ( filename ) ; return false ; } if ( ! externalStorageStatus . equals ( Environment . MEDIA_MOUNTED ) ) { if ( externalStorageStatus . equals ( Environment . MEDIA_SHARED ) ) { Log . e ( TAG , "Download failed: SD card unavailable" ) ; } else { Log . e ( TAG , "Download failed: no SD card" ) ; } alertDownloadFailure ( filename ) ; return false ; } return true ; }
target:  Check the external storage and notify user on error.