Enable options to remap CapsLock whenever an external keyboard is connected.

chrome/browser/ui/webui/options/chromeos/keyboard_handler.cc

 // Copyright (c) 2012 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/options/chromeos/keyboard_handler.h"
 
 #include "ash/new_window_delegate.h"
 #include "ash/shell.h"
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/values.h"
 #include "chrome/grit/generated_resources.h"
 #include "chromeos/chromeos_switches.h"
 #include "content/public/browser/web_ui.h"
 #include "ui/base/ime/chromeos/ime_keyboard.h"
 #include "ui/base/l10n/l10n_util.h"
+#include "ui/events/devices/device_data_manager.h"
+#include "ui/events/devices/keyboard_device.h"
 
 namespace {
 const struct ModifierKeysSelectItem {
   int message_id;
   chromeos::input_method::ModifierKey value;
 } kModifierKeysSelectItems[] = {
   { IDS_OPTIONS_SETTINGS_LANGUAGES_KEY_SEARCH,
     chromeos::input_method::kSearchKey },
   { IDS_OPTIONS_SETTINGS_LANGUAGES_KEY_LEFT_CTRL,
     chromeos::input_method::kControlKey },
   { IDS_OPTIONS_SETTINGS_LANGUAGES_KEY_LEFT_ALT,
     chromeos::input_method::kAltKey },
   { IDS_OPTIONS_SETTINGS_LANGUAGES_KEY_VOID,
     chromeos::input_method::kVoidKey },
   { IDS_OPTIONS_SETTINGS_LANGUAGES_KEY_CAPS_LOCK,
     chromeos::input_method::kCapsLockKey },
   { IDS_OPTIONS_SETTINGS_LANGUAGES_KEY_ESCAPE,
     chromeos::input_method::kEscapeKey },
 };
 
 const char* kDataValuesNames[] = {
   "remapSearchKeyToValue",
   "remapControlKeyToValue",
   "remapAltKeyToValue",
   "remapCapsLockKeyToValue",
   "remapDiamondKeyToValue",
 };
+
+bool HasExternalKeyboard() {
+  for (const ui::KeyboardDevice& keyboard :
+       ui::DeviceDataManager::GetInstance()->keyboard_devices()) {
+    if (keyboard.type == ui::InputDeviceType::INPUT_DEVICE_EXTERNAL)
+      return true;
+  }
+
+  return false;
+}
 }  // namespace
 
 namespace chromeos {
 namespace options {
 
 KeyboardHandler::KeyboardHandler() {
+  ui::DeviceDataManager::GetInstance()->AddObserver(this);
 }
 
 KeyboardHandler::~KeyboardHandler() {
+  ui::DeviceDataManager::GetInstance()->RemoveObserver(this);
 }
 
 void KeyboardHandler::GetLocalizedValues(
     base::DictionaryValue* localized_strings) {
   DCHECK(localized_strings);
   RegisterTitle(localized_strings, "keyboardOverlay",
                 IDS_OPTIONS_KEYBOARD_OVERLAY_TITLE);
 
   localized_strings->SetString("remapSearchKeyToContent",
       l10n_util::GetStringUTF16(
@@ skipping 60 matching lines @@
       option->Append(new base::FundamentalValue(value));
       option->Append(new base::StringValue(l10n_util::GetStringUTF16(
           message_id)));
       list_value->Append(option);
     }
     localized_strings->Set(kDataValuesNames[i], list_value);
   }
 }
 
 void KeyboardHandler::InitializePage() {
-  bool chromeos_keyboard = base::CommandLine::ForCurrentProcess()->HasSwitch(
-      chromeos::switches::kHasChromeOSKeyboard);

[Jun Mukai, 2015/06/15 23:57:25]

Do we need to keep this flag?
It looks like:
- defined in chromeos/chromeos_switches
- used only here
- referred in chrome/browser/chromeos/login/chrome_restart_request.cc, but it
looks like just copying the flag existence.
- chrome/browser/chromeos/events/event_rewriter_unittest.cc refers this flag,
but I'm not sure how this affects the test.


My bet is that this flag is almost deprecated, and you've removed the last
usage. If that's true, you can safely remove this flag itself.
You can remove the flag in another CL though.

[afakhry, 2015/06/16 00:52:47]

Yes I noticed that this flag is no longer used, but I wasn't sure if I should
remove it or if its removal should be part of this CL. I think I can remove it
in a follow-up CL as you suggested.

-  const base::FundamentalValue show_caps_lock_options(!chromeos_keyboard);
-
   bool has_diamond_key = base::CommandLine::ForCurrentProcess()->HasSwitch(
       chromeos::switches::kHasChromeOSDiamondKey);
   const base::FundamentalValue show_diamond_key_options(has_diamond_key);
 
   web_ui()->CallJavascriptFunction(
-      "options.KeyboardOverlay.showCapsLockOptions",
-      show_caps_lock_options);
-  web_ui()->CallJavascriptFunction(
       "options.KeyboardOverlay.showDiamondKeyOptions",
       show_diamond_key_options);
+
+  UpdateCapsLockOptions();
 }
 
 void KeyboardHandler::RegisterMessages() {
   // Callback to show keyboard overlay.
   web_ui()->RegisterMessageCallback(
       "showKeyboardShortcuts",
       base::Bind(&KeyboardHandler::HandleShowKeyboardShortcuts,
                  base::Unretained(this)));
 }
 
+void KeyboardHandler::OnKeyboardDeviceConfigurationChanged() {
+  UpdateCapsLockOptions();
+}
+
 void KeyboardHandler::HandleShowKeyboardShortcuts(const base::ListValue* args) {
   ash::Shell::GetInstance()->new_window_delegate()->ShowKeyboardOverlay();
 }
 
+void KeyboardHandler::UpdateCapsLockOptions() const {
+  const base::FundamentalValue show_caps_lock_options(HasExternalKeyboard());
+  web_ui()->CallJavascriptFunction(
+      "options.KeyboardOverlay.showCapsLockOptions",
+      show_caps_lock_options);
+}
+
 }  // namespace options
 }  // namespace chromeos