I write some little gtalk client using Smack. I want to implement the invisible feature, as exist in the gmail gtalk client (does anybody know why it is not existed in the full gtalk client of google??), and I could not feague out a way to do so yet, though I googled all around the web. It must be possible - since we see it in gmail . Does anybody know how?
I also would like to retrieve from the google server lists of the user hidden and blocked contacts. I tried to use the Privacy of Smack, but when running it I got something like “feature is not implemented (501)”. I guess it means that the google server does not implement this(?)
Do you know how to do it? I noticed that when receiving the roster from the server I see only not-hidden users (which is not the case in other XMPP libraries that I tried), so Smack probably aware of whether a user is hidden or not.