How can an object that processes asynchronous requests notify the external environment about its actions?

Question

C++ / C#

I am writing a WinRT application in C#.
The "server" object handles requests, and every time a client connects, the UI needs to be updated.
Can this be done only with the Observer pattern (use events) or are there other approaches?

Answer 1

WCF - обратный вызов на клиенте.
SignalR - тоже самое, callback.
Клиент может сам каждую секунду получать новые данные.