HRESULT XGameStreamingRegisterConnectionStateChanged(  
         XTaskQueueHandle queue,  
         void* context,  
         XGameStreamingConnectionStateChangedCallback* callback,  
         XTaskQueueRegistrationToken* token  
)  

    // Called during game startup to hook into any game streaming start/stop events
    void SetupStreamAware()
    {
        // Register a callback for client connections and disconnections. Note that the connection callback
        // will fire for any already connected clients, so do all of our per-client setup in that callback.      
        XGameStreamingConnectionStateChangedRegistrationToken stateChangeToken = {0};
        XGameStreamingRegisterConnectionStateChanged(
            m_taskQueue, this, ConnectionStateChangedCallback, &stateChangeToken);
    }

    static void ConnectionStateChangedCallback(void* context, XGameStreamingClientId client, XGameStreamingConnectionState state)
    {
        static_cast<Game*>(context)->OnConnectionStateChanged(client, state);
    }

    void OnConnectionStateChanged(XGameStreamingClientId client, XGameStreamingConnectionState state)
    {
        switch (state)
        {
        case XGameStreamingConnectionState::Connected: 
            OnClientConnected(client); 
            break;
        case XGameStreamingConnectionState::Disconnected: 
            OnClientDisconnected(client); 
            break;
        default: 
            break;
        }
    }


    void OnClientConnected(XGameStreamingClientId client)
    {
        // Update list of connected clients
        m_streamingClients.push_back(client);

        // Do per-client initialization
        // ...
    }

    void OnClientDisconnected(XGameStreamingClientId client)
    {
        // Release our reference on the client that is no longer streaming the game
        std::remove(m_streamingClients.begin(), m_streamingClients.end(), client);

        // Do per-client cleanup
        // ...
    }