a11y/Mac: Add screenreader support for SubtleNotificationView announcements.

chrome/browser/ui/views/subtle_notification_view.cc

 // Copyright 2016 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/views/subtle_notification_view.h"
 
 #include <memory>
 
 #include "base/strings/string_split.h"
 #include "base/strings/utf_string_conversions.h"
 #include "third_party/skia/include/core/SkColor.h"
+#include "ui/accessibility/ax_view_state.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/font_list.h"
 #include "ui/views/bubble/bubble_border.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/controls/link.h"
 #include "ui/views/layout/box_layout.h"
 #include "ui/views/widget/widget.h"
 
 namespace {
 
@@ skipping 20 matching lines @@
  public:
   // Creates an InstructionView with specific text. |text| may contain one or
   // more segments delimited by a pair of pipes ('|'); each of these segments
   // will be displayed as a keyboard key. e.g., "Press |Alt|+|Q| to exit" will
   // have "Alt" and "Q" rendered as keys.
   InstructionView(const base::string16& text,
                   const gfx::FontList& font_list,
                   SkColor foreground_color,
                   SkColor background_color);
 
+  base::string16 text();

[tapted, 2016/06/22 00:23:38]

nit: declare const function

[Patti Lor, 2016/06/23 01:00:38]

Done.

   void SetText(const base::string16& text);
 
  private:
   // Adds a label to the end of the notification text. If |format_as_key|,
   // surrounds the label in a rounded-rect border to indicate that it is a
   // keyboard key.
   void AddTextSegment(const base::string16& text, bool format_as_key);
 
   const gfx::FontList& font_list_;
   SkColor foreground_color_;
@@ skipping 13 matching lines @@
       foreground_color_(foreground_color),
       background_color_(background_color) {
   // The |between_child_spacing| is the horizontal margin of the key name.
   views::BoxLayout* layout = new views::BoxLayout(views::BoxLayout::kHorizontal,
                                                   0, 0, kKeyNameMarginHorizPx);
   SetLayoutManager(layout);
 
   SetText(text);
 }
 
+base::string16 SubtleNotificationView::InstructionView::text() {
+  return text_;

[tapted, 2016/06/22 00:23:38]

nit: declare this inline

[Matt Giuca, 2016/06/22 02:59:20]

This needs to have the pipes removed
(http://www.officeworks.com.au/shop/officeworks/c/school-art/craft-materials/p...
?) before being read aloud.

Few approaches:
1. Change have text() clean the pipes out of this string, and rename to
GetText() to show that it's non-trivial.
2. Have GetAccessibleState do it. (Probably preferred; it's a bit weird that
GetText() does not return what SetText() receives.)

[Patti Lor, 2016/06/23 01:00:38]

Done (as per option 2).

+}
+
 void SubtleNotificationView::InstructionView::SetText(
     const base::string16& text) {
   // Avoid replacing the contents with the same text.
   if (text == text_)
     return;
 
   RemoveAllChildViews(true);
 
   // Parse |text|, looking for pipe-delimited segment.
   std::vector<base::string16> segments =
@@ skipping 106 matching lines @@
   // We set layout manager to nullptr to prevent the widget from sizing its
   // contents to the same size as itself. This prevents the widget contents from
   // shrinking while we animate the height of the popup to give the impression
   // that it is sliding off the top of the screen.
   // TODO(mgiuca): This probably isn't necessary now that there is no slide
   // animation. Remove it.
   popup->GetRootView()->SetLayoutManager(nullptr);
 
   return popup;
 }
+
+// views::View:

[tapted, 2016/06/22 00:23:38]

nit: no need for this comment

[Patti Lor, 2016/06/23 01:00:39]

Done.

+
+void SubtleNotificationView::GetAccessibleState(ui::AXViewState* state) {
+  state->role = ui::AX_ROLE_LABEL_TEXT;
+  state->name = instruction_view_->text();

[Matt Giuca, 2016/06/22 02:59:20]

This needs to have the pipes removed
(http://www.officeworks.com.au/shop/officeworks/c/school-art/craft-materials/p...
?) before being read aloud. See SetText.

Alternatively, could have a method on InstructionView that returns the text
without pipes (but don't call it GetText, that would be confusing considering
SetText is called with pipes).

[Patti Lor, 2016/06/23 01:00:38]

Done.

+}