Add a new audio extension event OnLevelChanged.

extensions/browser/api/audio/audio_service_chromeos.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 "extensions/browser/api/audio/audio_service.h"
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
 #include "base/strings/string_number_conversions.h"
 #include "chromeos/audio/audio_device.h"
 #include "chromeos/audio/cras_audio_handler.h"
 #include "content/public/browser/browser_thread.h"
 
 using content::BrowserThread;
 
 namespace extensions {
 
 using core_api::audio::OutputDeviceInfo;
 using core_api::audio::InputDeviceInfo;
+using core_api::audio::AudioDeviceInfo;
 
 class AudioServiceImpl : public AudioService,
                          public chromeos::CrasAudioHandler::AudioObserver {
  public:
   AudioServiceImpl();
   ~AudioServiceImpl() override;
 
   // Called by listeners to this service to add/remove themselves as observers.
   void AddObserver(AudioService::Observer* observer) override;
   void RemoveObserver(AudioService::Observer* observer) override;
 
   // Start to query audio device information.
   void StartGetInfo(const GetInfoCallback& callback) override;
   void SetActiveDevices(const DeviceIdList& device_list) override;
   bool SetDeviceProperties(const std::string& device_id,
                            bool muted,
                            int volume,
                            int gain) override;
+  void StartGetDeviceInfo(const GetDeviceInfoCallback& callback) override;
 
  protected:
   // chromeos::CrasAudioHandler::AudioObserver overrides.
-  void OnOutputVolumeChanged() override;
+  void OnOutputNodeVolumeChanged(uint64 id, double volume) override;
   void OnInputGainChanged() override;
   void OnOutputMuteChanged() override;
   void OnInputMuteChanged() override;
   void OnAudioNodesChanged() override;
   void OnActiveOutputNodeChanged() override;
   void OnActiveInputNodeChanged() override;
 
  private:
   void NotifyDeviceChanged();
 
@@ skipping 111 matching lines @@
     cras_audio_handler_->SetVolumeGainPercentForDevice(device.id, volume);
     return true;
   } else if (device.is_input && gain != -1) {
     cras_audio_handler_->SetVolumeGainPercentForDevice(device.id, gain);
     return true;
   }
 
   return false;
 }
 
+void AudioServiceImpl::StartGetDeviceInfo(
+    const GetDeviceInfoCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  DCHECK(cras_audio_handler_);
+  DCHECK(!callback.is_null());
+
+  if (callback.is_null())
+    return;
+
+  DevicesInfo devices_info;
+  if (!cras_audio_handler_) {
+    callback.Run(devices_info, false);
+    return;
+  }
+
+  chromeos::AudioDeviceList devices;
+  cras_audio_handler_->GetAudioDevices(&devices);
+  for (size_t i = 0; i < devices.size(); ++i) {
+    linked_ptr<AudioDeviceInfo> info(new AudioDeviceInfo());
+    info->id = base::Uint64ToString(devices[i].id);
+    info->display_name = devices[i].display_name;
+    info->device_name = devices[i].device_name;
+    info->is_input = devices[i].is_input;
+    info->is_active = devices[i].active;
+    info->volume_gain =
+        devices[i].is_input
+            ? cras_audio_handler_->GetInputGainPercentForDevice(devices[i].id)
+            : cras_audio_handler_->GetOutputVolumePercentForDevice(
+                  devices[i].id);
+    info->is_muted =
+        devices[i].is_input
+            ? cras_audio_handler_->IsInputMutedForDevice(devices[i].id)
+            : cras_audio_handler_->IsOutputMutedForDevice(devices[i].id);
+    devices_info.push_back(info);
+  }
+
+  callback.Run(devices_info, true);
+}
+
 bool AudioServiceImpl::FindDevice(uint64 id, chromeos::AudioDevice* device) {
   chromeos::AudioDeviceList devices;
   cras_audio_handler_->GetAudioDevices(&devices);
 
   for (size_t i = 0; i < devices.size(); ++i) {
     if (devices[i].id == id) {
       *device = devices[i];
       return true;
     }
   }
   return false;
 }
 
 uint64 AudioServiceImpl::GetIdFromStr(const std::string& id_str) {
   uint64 device_id;
   if (!base::StringToUint64(id_str, &device_id))
     return 0;
   else
     return device_id;
 }
 
-void AudioServiceImpl::OnOutputVolumeChanged() {
+void AudioServiceImpl::OnOutputNodeVolumeChanged(uint64 id, double volume) {
+  FOR_EACH_OBSERVER(
+      AudioService::Observer, observer_list_,
+      OnOutputNodeVolumeChanged(base::Uint64ToString(id), volume));
+
+  // Notify DeviceChanged event for backward compatibility.
+  // TODO(jennyz): remove this code when the old version of hotrod retires.
   NotifyDeviceChanged();
 }
 
 void AudioServiceImpl::OnOutputMuteChanged() {
   NotifyDeviceChanged();
 }
 
 void AudioServiceImpl::OnInputGainChanged() {
   NotifyDeviceChanged();
 }
@@ skipping 16 matching lines @@
 
 void AudioServiceImpl::NotifyDeviceChanged() {
   FOR_EACH_OBSERVER(AudioService::Observer, observer_list_, OnDeviceChanged());
 }
 
 AudioService* AudioService::CreateInstance() {
   return new AudioServiceImpl;
 }
 
 }  // namespace extensions