Implement web speech synthesis.

content/renderer/tts_dispatcher.h

+// Copyright (c) 2013 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 CONTENT_RENDERER_TTS_DISPATCHER_H_
+#define CONTENT_RENDERER_TTS_DISPATCHER_H_
+
+#include <vector>
+
+#include "base/basictypes.h"
+#include "content/public/renderer/render_view_observer.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebSpeechSynthesis.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebSpeechSynthesisClient.h"
+
+namespace content {
+class RenderViewImpl;
+struct TtsVoice;
+
+// TtsDispatcher is a delegate for methods used by WebKit for
+// speech synthesis APIs. It's the complement of
+// TtsDispatcherHost (owned by RenderViewHost).
+class TtsDispatcher : public RenderViewObserver,
+                      public WebKit::WebSpeechSynthesis {
+ public:
+  explicit TtsDispatcher(RenderViewImpl* render_view);
+  virtual ~TtsDispatcher();
+
+ private:
+  // RenderViewObserver implementation.
+  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
+
+  // WebKit::WebSpeechSynthesis implementation.
+  virtual void setClient(WebKit::WebSpeechSynthesisClient* client) OVERRIDE;
+  virtual void initializeVoiceList() OVERRIDE;
+  virtual void speak(const WebKit::WebSpeechSynthesisUtterance& utterance)
+      OVERRIDE;
+  virtual void pause() OVERRIDE;
+  virtual void resume() OVERRIDE;
+  virtual void cancel() OVERRIDE;
+
+  void OnSetVoiceList(const std::vector<content::TtsVoice>& voices);
+  void OnDidStartSpeaking(int utterance_id);
+  void OnDidFinishSpeaking(int utterance_id);
+  void OnDidPauseSpeaking(int utterance_id);
+  void OnDidResumeSpeaking(int utterance_id);
+  void OnWordBoundary(int utterance_id, int char_index);
+  void OnSentenceBoundary(int utterance_id, int char_index);
+  void OnMarkerEvent(int utterance_id, int char_index);
+  void OnWasInterrupted(int utterance_id);
+  void OnWasCancelled(int utterance_id);
+  void OnSpeakingErrorOccurred(int utterance_id,
+                               const std::string& error_message);
+
+  // The WebKit client class that we use to send events back to the JS world.
+  WebKit::WebSpeechSynthesisClient* synthesis_client_;

[tommi (sloooow) - chröme, 2013/03/07 13:04:46]

document ownership/scope?

[dmazzoni, 2013/03/19 17:30:22]

Done.

+
+  DISALLOW_COPY_AND_ASSIGN(TtsDispatcher);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_TTS_DISPATCHER_H_