Side Slide Gestures for Accessibility

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/audio/sounds.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/host/ash_window_tree_host.h"
 #include "ash/root_window_settings.h"
 #include "ash/session/session_state_delegate.h"
 #include "ash/shelf/shelf_layout_manager.h"
@@ skipping 22 matching lines @@
 #include "ash/wm/status_area_layout_manager.h"
 #include "ash/wm/system_background_controller.h"
 #include "ash/wm/system_modal_container_layout_manager.h"
 #include "ash/wm/window_properties.h"
 #include "ash/wm/window_state.h"
 #include "ash/wm/window_util.h"
 #include "ash/wm/workspace/workspace_layout_manager.h"
 #include "ash/wm/workspace_controller.h"
 #include "base/command_line.h"
 #include "base/time/time.h"
+#include "chromeos/audio/chromeos_sounds.h"

[James Cook, 2014/07/14 17:19:31]

Ash code is compile on non-ChromeOS platforms (e.g. Windows) so this and all
code that uses it needs to be in #if defined(OS_CHROMEOS).

[lisayin, 2014/07/14 22:38:38]

Done.

+#include "chromeos/audio/cras_audio_handler.h"
+#include "chromeos/chromeos_switches.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/screen_position_client.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_delegate.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/aura/window_observer.h"
 #include "ui/aura/window_tracker.h"
 #include "ui/base/hit_test.h"
 #include "ui/base/models/menu_model.h"
 #include "ui/gfx/display.h"
@@ skipping 193 matching lines @@
   }
   virtual void GetHitTestMask(gfx::Path* mask) const OVERRIDE {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(EmptyWindowDelegate);
 };
 
 #if defined(OS_CHROMEOS)
 // Responsible for initializing TouchExplorationController when spoken
 // feedback is on.
-class CrosAccessibilityObserver : public AccessibilityObserver {
+class CrosAccessibilityObserver

[James Cook, 2014/07/14 17:19:30]

Please extract this class into its own file.  It's a little too big for a
platform-specific local class. This will also let you use GYP to exclude it on
non-Chrome OS platforms and reduce the number of headers this file needs to
include.

This would also make it easier to add a small test for this, especially if you
inject your own mock CrasAudioHandler.

[dmazzoni, 2014/07/14 18:00:33]

That sounds good to me. I'd call it something like AshTouchExplorationManager or
something like that, since "accessibility observer" doesn't really describe its
primary purpose.

[lisayin, 2014/07/14 22:40:36]

Should the file be in the same folder as this file?

+    : public AccessibilityObserver,
+      public ui::TouchExplorationControllerDelegate {
  public:
   explicit CrosAccessibilityObserver(
       RootWindowController* root_window_controller)
-      : root_window_controller_(root_window_controller) {
+      : root_window_controller_(root_window_controller),
+        audio_handler_(chromeos::CrasAudioHandler::Get()) {
     Shell::GetInstance()->system_tray_notifier()->
         AddAccessibilityObserver(this);
     UpdateTouchExplorationState();
   }
 
   virtual ~CrosAccessibilityObserver() {
     SystemTrayNotifier* system_tray_notifier =
         Shell::GetInstance()->system_tray_notifier();
     if (system_tray_notifier)
       system_tray_notifier->RemoveAccessibilityObserver(this);
   }
 
+  bool VolumeAdjustSoundEnabled() {

[James Cook, 2014/07/14 17:19:30]

const?

[lisayin, 2014/07/14 22:38:38]

Done.

+    return !CommandLine::ForCurrentProcess()->HasSwitch(
+        chromeos::switches::kDisableVolumeAdjustSound);
+  }
+
+  // Overridden from TouchExplorationControllerDelegate

[James Cook, 2014/07/14 17:19:30]

nit: end with colon

[lisayin, 2014/07/14 22:38:38]

Done.

+  virtual void PlayVolumeAdjustSound() OVERRIDE{
+    if (!VolumeAdjustSoundEnabled())
+      return;
+
+    if (!audio_handler_->IsOutputMuted() ||
+        !audio_handler_->GetOutputVolumePercent() == 100)
+      PlaySystemSoundIfSpokenFeedback(chromeos::SOUND_VOLUME_ADJUST);
+  }
+
+  // Overridden from TouchExplorationControllerDelegate

[James Cook, 2014/07/14 17:19:30]

nit: We usually only have one of these lines

[lisayin, 2014/07/14 22:38:38]

Done.

+  virtual void AdjustSound(float volume) OVERRIDE {
+    if (volume > 0) {
+      if (audio_handler_->IsOutputMuted()) {
+        audio_handler_->SetOutputMute(false);
+      }
+    }
+    audio_handler_->SetOutputVolumePercent(volume);
+    // Avoid negative volume.
+    if (audio_handler_->IsOutputVolumeBelowDefaultMuteLvel())

[James Cook, 2014/07/14 17:19:31]

Not your typo, but could you use this CL to change the name of this function to
"IsOutputVolumeBelowDefaultMuteLevel"?

+      audio_handler_->SetOutputMute(true);
+  }
+
  private:
   void UpdateTouchExplorationState() {
     AccessibilityDelegate* delegate =
         Shell::GetInstance()->accessibility_delegate();
     bool enabled = delegate->IsSpokenFeedbackEnabled();
 
     if (enabled && !touch_exploration_controller_.get()) {
-      touch_exploration_controller_.reset(
-          new ui::TouchExplorationController(
-              root_window_controller_->GetRootWindow()));
+      touch_exploration_controller_.reset(new ui::TouchExplorationController(
+          root_window_controller_->GetRootWindow(), this));
     } else if (!enabled) {
       touch_exploration_controller_.reset();
     }
   }
 
   // Overridden from AccessibilityObserver.
   virtual void OnAccessibilityModeChanged(
       AccessibilityNotificationVisibility notify) OVERRIDE {
     UpdateTouchExplorationState();
   }
 
   scoped_ptr<ui::TouchExplorationController> touch_exploration_controller_;
   RootWindowController* root_window_controller_;
+  chromeos::CrasAudioHandler* audio_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(CrosAccessibilityObserver);
 };
 #endif  // OS_CHROMEOS
 
 }  // namespace
 
 void RootWindowController::CreateForPrimaryDisplay(AshWindowTreeHost* host) {
   RootWindowController* controller = new RootWindowController(host);
   controller->Init(RootWindowController::PRIMARY,
@@ skipping 794 matching lines @@
   else
     DisableTouchHudProjection();
 }
 
 RootWindowController* GetRootWindowController(
     const aura::Window* root_window) {
   return root_window ? GetRootWindowSettings(root_window)->controller : NULL;
 }
 
 }  // namespace ash