Connecting webrtc-internals WebUI frontend with the backend

chrome/browser/ui/webui/media/webrtc_internals_proxy.cc

+// 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.
+
+#include "chrome/browser/ui/webui/media/webrtc_internals_proxy.h"
+
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/media/webrtc_internals.h"
+#include "chrome/browser/ui/webui/media/webrtc_internals_message_handler.h"
+#include "content/public/browser/web_ui.h"
+
+using content::BrowserThread;
+using media::WebRTCInternals;
+
+WebRTCInternalsProxy::WebRTCInternalsProxy() {}
+
+void WebRTCInternalsProxy::OnUpdate(const std::string& command,
+                                    const base::Value* args) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  std::vector<const Value*> args_vector;
+  args_vector.push_back(args);
+  string16 update = content::WebUI::GetJavascriptCall(command, args_vector);
+
+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      base::Bind(&WebRTCInternalsProxy::UpdateOnUIThread, this, update));
+}
+
+void WebRTCInternalsProxy::Attach(WebRTCInternalsMessageHandler* handler) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  handler_ = handler;
+  BrowserThread::PostTask(
+      BrowserThread::IO, FROM_HERE,
+      base::Bind(&WebRTCInternalsProxy::ObserveWebRTCInternalsOnIOThread,
+                 this));
+}
+
+void WebRTCInternalsProxy::Detach() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  handler_ = NULL;
+  BrowserThread::PostTask(
+      BrowserThread::IO, FROM_HERE,
+      base::Bind(
+          &WebRTCInternalsProxy::StopObservingWebRTCInternalsOnIOThread, this));
+}
+
+WebRTCInternalsProxy::~WebRTCInternalsProxy() {}
+
+void WebRTCInternalsProxy::ObserveWebRTCInternalsOnIOThread() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  WebRTCInternals::GetInstance()->AddObserver(this);
+}
+
+void WebRTCInternalsProxy::StopObservingWebRTCInternalsOnIOThread() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  WebRTCInternals::GetInstance()->RemoveObserver(this);
+}
+
+void WebRTCInternalsProxy::UpdateOnUIThread(const string16& update) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (handler_)
+    handler_->OnUpdate(update);
+}