First crack at implementing the touch explaration mode.

ash/root_window_controller.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 "ash/root_window_controller.h"
 
 #include <queue>
 #include <vector>
 
 #include "ash/ash_constants.h"
 #include "ash/ash_switches.h"
 #include "ash/desktop_background/desktop_background_controller.h"
 #include "ash/desktop_background/desktop_background_widget_controller.h"
 #include "ash/desktop_background/user_wallpaper_delegate.h"
 #include "ash/display/display_manager.h"
 #include "ash/focus_cycler.h"
 #include "ash/high_contrast/high_contrast_controller.h"
 #include "ash/root_window_settings.h"
 #include "ash/session_state_delegate.h"
 #include "ash/shelf/shelf_layout_manager.h"
 #include "ash/shelf/shelf_types.h"
 #include "ash/shelf/shelf_widget.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
 #include "ash/shell_factory.h"
 #include "ash/shell_window_ids.h"
 #include "ash/switchable_windows.h"
 #include "ash/system/status_area_widget.h"
 #include "ash/system/tray/system_tray_delegate.h"
+#include "ash/system/tray/system_tray_notifier.h"
 #include "ash/touch/touch_hud_debug.h"
 #include "ash/touch/touch_hud_projection.h"
 #include "ash/touch/touch_observer_hud.h"
 #include "ash/wm/always_on_top_controller.h"
 #include "ash/wm/dock/docked_window_layout_manager.h"
 #include "ash/wm/panels/panel_layout_manager.h"
 #include "ash/wm/panels/panel_window_event_handler.h"
 #include "ash/wm/root_window_layout_manager.h"
 #include "ash/wm/screen_dimmer.h"
 #include "ash/wm/stacking_controller.h"
@@ skipping 666 matching lines @@
   } else {
     root_window_layout()->OnWindowResized();
     shell->desktop_background_controller()->OnRootWindowAdded(root_window());
     shell->high_contrast_controller()->OnRootWindowAdded(root_window());
     host_->Show();
 
     // Create a shelf if a user is already logged in.
     if (shell->session_state_delegate()->NumberOfLoggedInUsers())
       shelf()->CreateShelf();
   }
+
+  Shell::GetInstance()->system_tray_notifier()->AddAccessibilityObserver(this);
+  UpdateTouchExplorationState();
 }
 
 void RootWindowController::InitLayoutManagers() {
   root_window_layout_ = new RootWindowLayoutManager(root_window());
   root_window()->SetLayoutManager(root_window_layout_);
 
   aura::Window* default_container =
       GetContainer(kShellWindowId_DefaultContainer);
   // Workspace manager has its own layout managers.
   workspace_controller_.reset(
@@ skipping 276 matching lines @@
   shelf_->shelf_layout_manager()->UpdateVisibilityState();
 }
 
 void RootWindowController::OnTouchHudProjectionToggled(bool enabled) {
   if (enabled)
     EnableTouchHudProjection();
   else
     DisableTouchHudProjection();
 }
 
+void RootWindowController::UpdateTouchExplorationState() {
+  AccessibilityDelegate* delegate =
+        Shell::GetInstance()->accessibility_delegate();
+  bool enabled = delegate->IsSpokenFeedbackEnabled();
+
+  LOG(ERROR) << "RWC::UpdateTouchExplorationState: enabled=" << enabled;
+
+  if (enabled && !touch_exploration_controller_.get()) {
+    touch_exploration_controller_.reset(
+        new TouchExplorationController(root_window()));
+  } else if (!enabled && touch_exploration_controller_.get()) {
+    touch_exploration_controller_.reset();
+  }
+}
+
+void RootWindowController::OnAccessibilityModeChanged(
+      AccessibilityNotificationVisibility notify) {
+  UpdateTouchExplorationState();
+}
+
 RootWindowController* GetRootWindowController(
     const aura::Window* root_window) {
   return root_window ? GetRootWindowSettings(root_window)->controller : NULL;
 }
 
 }  // namespace internal
 }  // namespace ash