1 // Copyright 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef COMPONENTS_SYNC_JS_JS_CONTROLLER_H_
6 #define COMPONENTS_SYNC_JS_JS_CONTROLLER_H_
7 
8 // See README for design comments.
9 
10 #include <string>
11 
12 namespace syncer {
13 
14 class JsEventHandler;
15 
16 // An interface for objects that JsEventHandlers directly interact
17 // with.  JsEventHandlers can add themselves to receive events and
18 // also send messages which will eventually reach the backend.
19 class JsController {
20  public:
21   // Adds an event handler which will start receiving JS events (not
22   // immediately, so this can be called in the handler's constructor).
23   // Multiple event handlers are supported, but each event handler
24   // must be added at most once.
25   //
26   // Ideally, we'd take WeakPtrs, but we need the raw pointer values
27   // to be able to look them up for removal.
28   virtual void AddJsEventHandler(JsEventHandler* event_handler) = 0;
29 
30   // Removes the given event handler if it has been added.  It will
31   // immediately stop receiving any JS events.
32   virtual void RemoveJsEventHandler(JsEventHandler* event_handler) = 0;
33 
34  protected:
~JsController()35   virtual ~JsController() {}
36 };
37 
38 }  // namespace syncer
39 
40 #endif  // COMPONENTS_SYNC_JS_JS_CONTROLLER_H_
41