question: @ Override public void onTransferProgress ( long progressRate , long totalTransferredSoFar , long totalToTransfer , String filePath ) { int percent = ( int ) ( 100.0 * ( ( double ) totalTransferredSoFar ) / ( ( double ) totalToTransfer ) ) ; if ( percent != mLastPercent ) { mNotificationBuilder . setProgress ( 100 , percent , totalToTransfer < 0 ) ; String fileName = filePath . substring ( filePath . lastIndexOf ( FileUtils . PATH_SEPARATOR ) + 1 ) ; String text = String . format ( getString ( R . string . downloader_download_in_progress_content ) , percent , fileName ) ; mNotificationBuilder . setContentText ( text ) ; mNotificationManager . notify ( R . string . downloader_download_in_progress_ticker , mNotificationBuilder . build ( ) ) ; } mLastPercent = percent ; }
target:  Callback method to update the progress bar in the status notification.