[Mac] Added Accessibility Labels to the Default Touch Bar

chrome/browser/ui/cocoa/browser_window_touch_bar.mm

 // Copyright 2017 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.
 
 #import "chrome/browser/ui/cocoa/browser_window_touch_bar.h"
 
 #include <memory>
 
 #include "base/mac/mac_util.h"
 #import "base/mac/scoped_nsobject.h"
 #import "base/mac/sdk_forward_declarations.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/strings/sys_string_conversions.h"
 #include "chrome/app/chrome_command_ids.h"
 #include "chrome/app/vector_icons/vector_icons.h"
 #include "chrome/browser/command_updater.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search_engines/template_url_service_factory.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_command_controller.h"
 #import "chrome/browser/ui/cocoa/browser_window_controller.h"
 #include "chrome/common/chrome_features.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/omnibox/browser/vector_icons.h"
 #include "components/prefs/pref_member.h"
 #include "components/search_engines/util.h"
+#include "components/strings/grit/components_strings.h"
 #include "components/toolbar/vector_icons.h"
 #include "ui/base/l10n/l10n_util.h"
+#include "ui/base/l10n/l10n_util_mac.h"
 #include "ui/gfx/color_palette.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/gfx/image/image.h"
 #include "ui/gfx/image/image_skia_util_mac.h"
 #include "ui/gfx/paint_vector_icon.h"
 #include "ui/vector_icons/vector_icons.h"
 
 namespace {
 
 // The touch bar actions that are being recorded in a histogram. These values
@@ skipping 42 matching lines @@
                                SkColor color = kTouchBarDefaultIconColor) {
   return NSImageFromImageSkiaWithColorSpace(
       gfx::CreateVectorIcon(icon, kTouchBarIconSize, color),
       base::mac::GetSRGBColorSpace());
 }
 
 // Creates a NSButton for the touch bar.
 NSButton* CreateTouchBarButton(const gfx::VectorIcon& icon,
                                BrowserWindowTouchBar* owner,
                                int command,
+                               int tooltip_id,
                                SkColor color = kTouchBarDefaultIconColor) {
   NSButton* button =
       [NSButton buttonWithImage:CreateNSImageFromIcon(icon, color)
                          target:owner
                          action:@selector(executeCommand:)];
   button.tag = command;
+  [button setAccessibilityLabel:l10n_util::GetNSString(tooltip_id)];
   return button;
 }
 
 TouchBarAction TouchBarActionFromCommand(int command) {
   switch (command) {
     case IDC_BACK:
       return TouchBarAction::BACK;
     case IDC_FORWARD:
       return TouchBarAction::FORWARD;
     case IDC_STOP:
@@ skipping 119 matching lines @@
   if (!touchBar)
     return nil;
 
   base::scoped_nsobject<NSCustomTouchBarItem> touchBarItem([[NSClassFromString(
       @"NSCustomTouchBarItem") alloc] initWithIdentifier:identifier]);
   if ([identifier isEqualTo:kBackForwardTouchId]) {
     [touchBarItem setView:[self backOrForwardTouchBarView]];
   } else if ([identifier isEqualTo:kReloadOrStopTouchId]) {
     const gfx::VectorIcon& icon =
         isPageLoading_ ? kNavigateStopIcon : kNavigateReloadIcon;
-    int command_id = isPageLoading_ ? IDC_STOP : IDC_RELOAD;
-    [touchBarItem setView:CreateTouchBarButton(icon, self, command_id)];
+    int commandId = isPageLoading_ ? IDC_STOP : IDC_RELOAD;
+    int tooltipId = isPageLoading_ ? IDS_TOOLTIP_STOP : IDS_TOOLTIP_RELOAD;
+    [touchBarItem
+        setView:CreateTouchBarButton(icon, self, commandId, tooltipId)];
   } else if ([identifier isEqualTo:kHomeTouchId]) {
+    [touchBarItem setView:CreateTouchBarButton(kNavigateHomeIcon, self,
+                                               IDC_HOME, IDS_TOOLTIP_HOME)];
+  } else if ([identifier isEqualTo:kNewTabTouchId]) {
     [touchBarItem
-        setView:CreateTouchBarButton(kNavigateHomeIcon, self, IDC_HOME)];
-  } else if ([identifier isEqualTo:kNewTabTouchId]) {
-    [touchBarItem setView:CreateTouchBarButton(kNewTabMacTouchbarIcon, self,
-                                               IDC_NEW_TAB)];
+        setView:CreateTouchBarButton(kNewTabMacTouchbarIcon, self, IDC_NEW_TAB,
+                                     IDS_TOOLTIP_NEW_TAB)];
   } else if ([identifier isEqualTo:kStarTouchId]) {
     const gfx::VectorIcon& icon =
         isStarred_ ? toolbar::kStarActiveIcon : toolbar::kStarIcon;
     SkColor iconColor =
         isStarred_ ? kTouchBarStarActiveColor : kTouchBarDefaultIconColor;
-    [touchBarItem
-        setView:CreateTouchBarButton(icon, self, IDC_BOOKMARK_PAGE, iconColor)];
+    int tooltipId = isStarred_ ? IDS_TOOLTIP_STARRED : IDS_TOOLTIP_STAR;
+    [touchBarItem setView:CreateTouchBarButton(icon, self, IDC_BOOKMARK_PAGE,
+                                               tooltipId, iconColor)];
   } else if ([identifier isEqualTo:kSearchTouchId]) {
     [touchBarItem setView:[self searchTouchBarView]];
   }
 
   return touchBarItem.autorelease();
 }
 
 - (NSView*)backOrForwardTouchBarView {
   NSArray* images = @[
     CreateNSImageFromIcon(ui::kBackArrowIcon),
     CreateNSImageFromIcon(ui::kForwardArrowIcon)
   ];
 
   NSSegmentedControl* control = [NSSegmentedControl
       segmentedControlWithImages:images
                     trackingMode:NSSegmentSwitchTrackingMomentary
                           target:self
                           action:@selector(backOrForward:)];
   control.segmentStyle = NSSegmentStyleSeparated;
   [control setEnabled:commandUpdater_->IsCommandEnabled(IDC_BACK)
            forSegment:kBackSegmentIndex];
   [control setEnabled:commandUpdater_->IsCommandEnabled(IDC_FORWARD)
            forSegment:kForwardSegmentIndex];
+
+  // Use the accessibility protocol to get the children.
+  // Use NSAccessibilityUnignoredDescendant to be sure we start with the correct
+  // object.
+  id segmentElement = NSAccessibilityUnignoredDescendant(control);
+  NSArray* segments = [segmentElement
+      accessibilityAttributeValue:NSAccessibilityChildrenAttribute];
+  NSEnumerator* e = [segments objectEnumerator];
+  [[e nextObject] accessibilitySetOverrideValue:l10n_util::GetNSString(
+                                                    IDS_TOOLTIP_TOUCH_BAR_BACK)
+                                   forAttribute:NSAccessibilityTitleAttribute];
+  [[e nextObject]
+      accessibilitySetOverrideValue:l10n_util::GetNSString(
+                                        IDS_TOOLTIP_TOUCH_BAR_FORWARD)
+                       forAttribute:NSAccessibilityTitleAttribute];
   return control;
 }
 
 - (NSView*)searchTouchBarView {
   TemplateURLService* templateUrlService =
       TemplateURLServiceFactory::GetForProfile(browser_->profile());
   const TemplateURL* defaultProvider =
       templateUrlService->GetDefaultSearchProvider();
   BOOL isGoogle =
       defaultProvider->GetEngineType(templateUrlService->search_terms_data()) ==
@@ skipping 35 matching lines @@
   commandUpdater_->ExecuteCommand(command);
 }
 
 - (void)executeCommand:(id)sender {
   int command = [sender tag];
   LogTouchBarUMA(command);
   commandUpdater_->ExecuteCommand(command);
 }
 
 @end