public async Task RequestRosterAsync()
{
var rosterIq = await xmppClient.RequestRosterAsync();
var rosterItems
= rosterIq
.Query
.Cast <Roster>()
.GetRoster();
await Observable.Start(() =>
{
foreach (var ri in rosterItems)
{
var contact = mapper.Map <Contact>(ri);
if (userAvatarStorage.HasUserAvatar(contact.Jid))
{
var hash = userAvatarStorage.GetUserAvatar(contact.Jid).Hash;
contact.AvatarBytes = avatarStorage.GetAvatar(hash)?.ImageBytes;
}
contacts.AddOrReplace(contact, c => c.Jid == contact.Jid);
}
}, RxApp.MainThreadScheduler);
}