a11y/Mac: Add screenreader support for SubtleNotificationView announcements.

chrome/browser/ui/views/subtle_notification_view.cc

Index: chrome/browser/ui/views/subtle_notification_view.cc
diff --git a/chrome/browser/ui/views/subtle_notification_view.cc b/chrome/browser/ui/views/subtle_notification_view.cc
index e922234e53cf93c417d23dd03f0c75e90bb06556..a7ba5c4ef5932989f99b3bda48057cf4167911ee 100644
--- a/chrome/browser/ui/views/subtle_notification_view.cc
+++ b/chrome/browser/ui/views/subtle_notification_view.cc
@@ -7,8 +7,10 @@
 #include <memory>
 
 #include "base/strings/string_split.h"
+#include "base/strings/string_util.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"
@@ -16,6 +18,7 @@
 #include "ui/views/controls/link.h"
 #include "ui/views/layout/box_layout.h"
 #include "ui/views/widget/widget.h"
+#include "ui/views/widget/widget_observer.h"
 
 namespace {
 
@@ -34,6 +37,9 @@ const int kKeyNameBorderPx = 1;
 const int kKeyNameCornerRadius = 2;
 const int kKeyNamePaddingPx = 5;
 
+// Delimiter indicating there should be a segment displayed as a keyboard key.
+const char kKeyNameDelimiter[] = "|";
+
 }  // namespace
 
 // Class containing the instruction text. Contains fancy styling on the keyboard
@@ -49,6 +55,7 @@ class SubtleNotificationView::InstructionView : public views::View {
                   SkColor foreground_color,
                   SkColor background_color);
 
+  base::string16 text() const { return text_; }
   void SetText(const base::string16& text);
 
  private:
@@ -92,8 +99,8 @@ void SubtleNotificationView::InstructionView::SetText(
 
   // Parse |text|, looking for pipe-delimited segment.
   std::vector<base::string16> segments =
-      base::SplitString(text, base::ASCIIToUTF16("|"), base::TRIM_WHITESPACE,
-                        base::SPLIT_WANT_ALL);
+      base::SplitString(text, base::ASCIIToUTF16(kKeyNameDelimiter),
+                        base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
   // SplitString() returns empty strings for zero-length segments, so given an
   // even number of pipes, there should always be an odd number of segments.
   // The exception is if |text| is entirely empty, in which case the returned
@@ -183,6 +190,9 @@ void SubtleNotificationView::UpdateContent(
   link_->SetText(link_text);
   link_->SetVisible(!link_text.empty());
   Layout();
+
+  NotifyAccessibilityEvent(ui::AX_EVENT_CHILDREN_CHANGED, true);
+  NotifyAccessibilityEvent(ui::AX_EVENT_ALERT, true);
 }
 
 // static
@@ -207,5 +217,40 @@ views::Widget* SubtleNotificationView::CreatePopupWidget(
   // animation. Remove it.
   popup->GetRootView()->SetLayoutManager(nullptr);
 
+  // Allow accessibility events to be sent when the view is shown.
+  popup->AddObserver(view);
+
   return popup;
 }
+
+void SubtleNotificationView::SetAccessibleName(
+    const base::string16& accessible_name) {
+  base::RemoveChars(accessible_name, base::ASCIIToUTF16(kKeyNameDelimiter),
+                    &accessible_name_);
+}
+
+void SubtleNotificationView::GetAccessibleState(ui::AXViewState* state) {
+  state->role = ui::AX_ROLE_LABEL_TEXT;
+
+  // If there is no accessible name set, use the displayed text, but ensure the
+  // '|' delimiters are removed.
+  if (accessible_name_.empty()) {
+    base::string16 accessible_name;
+    base::RemoveChars(instruction_view_->text(),
+                      base::ASCIIToUTF16(kKeyNameDelimiter), &accessible_name);
+    state->name = accessible_name;
+  } else {
+    state->name = accessible_name_;
+  }
+}
+
+void SubtleNotificationView::OnWidgetClosing(views::Widget* widget) {
+  if (widget && widget == GetWidget())
+    widget->RemoveObserver(this);
+}
+
+void SubtleNotificationView::OnWidgetVisibilityChanged(views::Widget* widget,
+                                                       bool visible) {
+  if (visible)
+    NotifyAccessibilityEvent(ui::AX_EVENT_ALERT, true);
+}