iOS Question AddVideoToAlbum how to?

How I can save my downloaded video to Album (Camera Roll)?

My code is:

In JobDone, after downloaded video url, I put:

Dim strDown As String = Job.GetString
Dim p As Phone
p.AddVideoToAlbum(strDown)


But not work, the method AddVideoToAlbum require (DIR and Filename) but where I can put the video?


Thanks