getFBProfilePicUrlAfterUpdate

 
  let loginManager: FBSDKLoginManager = FBSDKLoginManager()
            loginManager.logIn(withReadPermissions: ["user_link"], from: fromViewController) { (result, error) in
                if error != nil{
                    return
                }else if (result?.isCancelled)!{
                    //Handle cancelation
                }else{
                    if (result?.grantedPermissions.contains("user_link"))!{
                        //success
              getFBProfile()
                    }
                }
          }
 
 func getFBProfile(){
        let request = FBSDKGraphRequest(graphPath: "me", parameters: ["fields": "id, name, first_name, last_name, email, picture.type(large),link"])
        let _ = request?.start(completionHandler: { (connection, result, error) in
            guard let userInfo = result as? [String: Any] else { return }
            if let publicProfileLink = userInfo["link"] as? String {
              print("publicLink = \(publicProfileLink)")
                // publicProfileLink to access profile.
            }
            
        })
    }
      //publicLink = https://www.facebook.com/app_scoped_user_id/YXNpZADpBWEhkNUEzX2JBd2NfRkpJRklNX2NIUzB0Vm1lOGN4bTlaektKbUFwb1I4SWJzenRPZAXFlZAUJFM2J0SzVHZAXAyOXdhN1ZACVi1VVXZAJdVhrcl9DTmhrX0swLWRRTGttTktMaFR2SGZAwVWZAOdmwwQWFh/