Ratio of transferred to total between 0 and 1. If total is unknown, this is 0 until the download completes, then 1.
transferred
total
Total bytes to download, or null if the response had no Content-Length header.
null
Content-Length
Bytes downloaded so far.
Ratio of
transferredtototalbetween 0 and 1. Iftotalis unknown, this is 0 until the download completes, then 1.