Make MediaInternalsUI talk to MediaInternals.

chrome/browser/ui/webui/media_internals/media_internals_proxy.h

+// Copyright (c) 2011 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 CHROME_BROWSER_UI_WEBUI_MEDIA_INTERNALS_MEDIA_INTERNALS_PROXY_H_
+#define CHROME_BROWSER_UI_WEBUI_MEDIA_INTERNALS_MEDIA_INTERNALS_PROXY_H_
+#pragma once
+
+#include "base/string16.h"
+#include "base/memory/ref_counted.h"
+#include "chrome/browser/media/media_internals_observer.h"
+
+class IOThread;
+class MediaInternalsMessageHandler;
+
+// This class is a proxy between MediaInternals (on the IO thread) and
+// MediaInternalsMessageHandler (on the UI thread).
+// It is ref_counted to ensure that it completes all pending Tasks on both
+// threads before destruction.
+class MediaInternalsProxy
+    : public MediaInternalsObserver,
+      public base::RefCountedThreadSafe<MediaInternalsProxy> {
+ public:
+  MediaInternalsProxy();
+
+  // Register a Handler and start receiving callbacks from MediaInternals.
+  void Attach(MediaInternalsMessageHandler* handler);
+
+  // Unregister the same and stop receiving callbacks.
+  void Detach();
+
+  // Have MediaInternals send all the data it has.
+  void GetEverything();
+
+  // MediaInternalsObserver implementation. Called on the IO thread.
+  virtual void OnUpdate(const string16& update);
+
+ private:
+  friend class base::RefCountedThreadSafe<MediaInternalsProxy>;
+  virtual ~MediaInternalsProxy();
+
+  void ObserveMediaInternalsOnIOThread();
+  void StopObservingMediaInternalsOnIOThread();
+  void GetEverythingOnIOThread();
+  void UpdateUIOnUIThread(const string16& update);
+
+  MediaInternalsMessageHandler* handler_;
+  IOThread* io_thread_;
+
+  DISALLOW_COPY_AND_ASSIGN(MediaInternalsProxy);
+};
+
+#endif  // CHROME_BROWSER_UI_WEBUI_MEDIA_INTERNALS_MEDIA_INTERNALS_PROXY_H_