Propagate connection state from networking layer to UI.

remoting/protocol/connection_to_host.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef REMOTING_PROTOCOL_CONNECTION_TO_HOST_H_
 #define REMOTING_PROTOCOL_CONNECTION_TO_HOST_H_
 
 #include <string>
 
 #include "base/callback_forward.h"
@@ skipping 46 matching lines @@
     FAILED,
     CLOSED,
   };
 
   class HostEventCallback {
    public:
     virtual ~HostEventCallback() {}
 
     // Called when state of the connection changes.
     virtual void OnConnectionState(State state, ErrorCode error) = 0;
+
+    // Called to indicate inactive connection.

[Wez, 2012/07/16 18:51:23]

What does it mean for a connection to be "inactive"? I'd assume it means that
the client has not sent any input events for a while, or the host has sent no
video updates, but in the context of this CL it means that one or more channels
are not "connected"?

[Sergey Ulanov, 2012/07/17 01:17:17]

Done.

+    virtual void OnConnectionInactive(bool inactive) = 0;

[Wez, 2012/07/16 18:51:23]

Why not expose this as a new connection state?

[Sergey Ulanov, 2012/07/17 01:17:17]

I considered it, but I don't think it would be useful to expose it as part of
State:
 1. It's not really a part of the connection state machine implemented in this
class,
 2. Older version of the webapp may not know how to handle the new state state,
 3. Not all client will care about not-ready state,
 4. Later we may want to replace it with something that exposes more information
about connection health (e.g. delays, etc.).

   };
 
   ConnectionToHost(bool allow_nat_traversal);
   virtual ~ConnectionToHost();
 
   virtual void Connect(scoped_refptr<XmppProxy> xmpp_proxy,
                        const std::string& local_jid,
                        const std::string& host_jid,
                        const std::string& host_public_key,
                        scoped_ptr<TransportFactory> transport_factory,
@@ skipping 20 matching lines @@
   // SessionManager::Listener interface.
   virtual void OnSessionManagerReady() OVERRIDE;
   virtual void OnIncomingSession(
       Session* session,
       SessionManager::IncomingSessionResponse* response) OVERRIDE;
 
   // Session::EventHandler interface.
   virtual void OnSessionStateChange(Session::State state) OVERRIDE;
   virtual void OnSessionRouteChange(const std::string& channel_name,
                                     const TransportRoute& route) OVERRIDE;
+  virtual void OnSessionInactive(const std::string& channel_name,
+                                 bool inactive) OVERRIDE;
 
   // Return the current state of ConnectionToHost.
   State state() const;
 
  private:
   // Callbacks for channel initialization
   void OnChannelInitialized(bool successful);
 
   void NotifyIfChannelsReady();
 
@@ skipping 34 matching lines @@
   ErrorCode error_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ConnectionToHost);
 };
 
 }  // namespace protocol
 }  // namespace remoting
 
 #endif  // REMOTING_PROTOCOL_CONNECTION_TO_HOST_H_