Add persisted preference for projection touch HUD

chrome/browser/chromeos/preferences.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/chromeos/preferences.h"
 
 #include "ash/magnifier/magnifier_constants.h"
 #include "ash/shell_delegate.h"
 #include "base/chromeos/chromeos_version.h"
 #include "base/command_line.h"
@@ skipping 388 matching lines @@
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
   registry->RegisterDoublePref(
       prefs::kPowerUserActivityScreenDimDelayFactor,
       2.0,
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 
   registry->RegisterStringPref(
       prefs::kTermsOfServiceURL,
       "",
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
+
+  registry->RegisterBooleanPref(
+      prefs::kTouchHudProjectionEnabled,
+      false,
+      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 }
 
 void Preferences::InitUserPrefs(PrefServiceSyncable* prefs) {
   prefs_ = prefs;
 
   BooleanPrefMember::NamedChangeCallback callback =
       base::Bind(&Preferences::OnPreferenceChanged, base::Unretained(this));
 
   tap_to_click_enabled_.Init(prefs::kTapToClickEnabled, prefs, callback);
   tap_dragging_enabled_.Init(prefs::kTapDraggingEnabled, prefs, callback);
@@ skipping 19 matching lines @@
   disable_drive_over_cellular_.Init(prefs::kDisableDriveOverCellular,
                                     prefs, callback);
   disable_drive_hosted_files_.Init(prefs::kDisableDriveHostedFiles,
                                    prefs, callback);
   download_default_directory_.Init(prefs::kDownloadDefaultDirectory,
                                    prefs, callback);
   select_file_last_directory_.Init(prefs::kSelectFileLastDirectory,
                                    prefs, callback);
   save_file_default_directory_.Init(prefs::kSaveFileDefaultDirectory,
                                     prefs, callback);
+  touch_hud_projection_enabled_.Init(prefs::kTouchHudProjectionEnabled,
+                                     prefs, callback);
   primary_mouse_button_right_.Init(prefs::kPrimaryMouseButtonRight,
                                    prefs, callback);
   preferred_languages_.Init(prefs::kLanguagePreferredLanguages,
                             prefs, callback);
   preload_engines_.Init(prefs::kLanguagePreloadEngines, prefs, callback);
   enabled_extension_imes_.Init(prefs::kLanguageEnabledExtensionImes,
                                prefs, callback);
   current_input_method_.Init(prefs::kLanguageCurrentInputMethod,
                              prefs, callback);
   previous_input_method_.Init(prefs::kLanguagePreviousInputMethod,
@@ skipping 234 matching lines @@
   if (!pref_name || *pref_name == prefs::kSaveFileDefaultDirectory) {
     const base::FilePath pref_path = save_file_default_directory_.GetValue();
     // This pref can contain a Drive path, which needs to be updated due to
     // namespaces introduced by crbug.com/174233.
     // TODO(haruki): Remove this when migration completes. crbug.com/229304.
     if (drive::util::NeedsNamespaceMigration(pref_path)) {
       prefs_->SetFilePath(prefs::kSaveFileDefaultDirectory,
                           drive::util::ConvertToMyDriveNamespace(pref_path));
     }
   }
+  if (!pref_name || *pref_name == prefs::kTouchHudProjectionEnabled) {
+    const bool enabled = touch_hud_projection_enabled_.GetValue();
+    ash::Shell::GetInstance()->TouchHudProjectionEnabledChanged(enabled);

[sky, 2013/07/03 13:47:08]

Wouldn't all this be simpler if Shell had a
SetTouchHudProjectionEnabled(boolean); along with a delegate method
IsTouchUndProjectionEnabledChanged() ?

[mohsen, 2013/07/03 15:30:40]

Do you mean a SetTouchHudProjectionEnabled(boolean) in the preference side to be
called from the Ash side (through ShellDelegate) whenever user toggles
projection HUD on and off; and an IsTouchHudProjectionEnabledChanged() in the
Ash side to be called from the preferences side to notify Ash of changes in
preference? Then, we also need an IsTouchHudProjectionEnabled() in the
preference side to be called from the Ash side to get the current value of the
preference. Isn't it similar to current implementation? Or I'm misunderstanding
you!

+  }
 
   if (!pref_name || *pref_name == prefs::kLanguagePreferredLanguages) {
     // Unlike kLanguagePreloadEngines and some other input method
     // preferencs, we don't need to send this to ibus-daemon.
   }
 
   if (!pref_name || *pref_name == prefs::kLanguageXkbAutoRepeatEnabled) {
     const bool enabled = xkb_auto_repeat_enabled_.GetValue();
     input_method::XKeyboard::SetAutoRepeatEnabled(enabled);
   }
@@ skipping 301 matching lines @@
 
   input_method::AutoRepeatRate rate;
   rate.initial_delay_in_ms = xkb_auto_repeat_delay_pref_.GetValue();
   rate.repeat_interval_in_ms = xkb_auto_repeat_interval_pref_.GetValue();
   DCHECK(rate.initial_delay_in_ms > 0);
   DCHECK(rate.repeat_interval_in_ms > 0);
   input_method::XKeyboard::SetAutoRepeatRate(rate);
 }
 
 }  // namespace chromeos