MacViews: Implement Full Keyboard Access.

ui/views/focus/focus_manager.h

 // 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.
 
 #ifndef UI_VIEWS_FOCUS_FOCUS_MANAGER_H_
 #define UI_VIEWS_FOCUS_FOCUS_MANAGER_H_
 
 #include <list>
 #include <map>
 #include <memory>
@@ skipping 183 matching lines @@
   // attached to the window hierarchy anymore.
   void ValidateFocusedView();
 
   // Stores the focused view. Used when the widget loses activation.
   // |clear_native_focus| indicates whether this should invoke ClearFocus().
   // Typically |true| should be passed in.
   void StoreFocusedView(bool clear_native_focus);
 
   // Restore the view saved with a previous call to StoreFocusedView(). Used
   // when the widget becomes active. Returns true when the previous view was
-  // successfully refocused - otherwise false.
+  // successfully refocused. In case the stored view is no longer focusable,
+  // it advances focus and returns false.
   bool RestoreFocusedView();
 
   // Sets the |view| to be restored when calling RestoreFocusView. This is used
   // to set where the focus should go on restoring a Window created without
   // focus being set.
   void SetStoredFocusView(View* view);
 
   // Returns the View that either currently has focus, or if no view has focus
   // the view that last had focus.
   View* GetStoredFocusView();
@@ skipping 97 matching lines @@
   // |starting_view| is NULL |starting_widget| is consuled to determine which
   // Widget to start from. See
   // WidgetDelegate::ShouldAdvanceFocusToTopLevelWidget() for details. If both
   // |starting_view| and |starting_widget| are NULL, traversal starts at
   // |widget_|.
   View* GetNextFocusableView(View* starting_view,
                              Widget* starting_widget,
                              bool reverse,
                              bool dont_loop);
 
+  bool keyboard_accessible() const { return keyboard_accessible_; }
+
+  // Updates |keyboard_accessible_| to the given value and advances focus if
+  // necessary.
+  void SetKeyboardAccessible(bool keyboard_accessible);
+
  private:
   // Returns the focusable view found in the FocusTraversable specified starting
   // at the specified view. This traverses down along the FocusTraversable
   // hierarchy.
   // Returns NULL if no focusable view were found.
   View* FindFocusableView(FocusTraversable* focus_traversable,
                           View* starting_view,
                           bool reverse);
 
   // Process arrow key traversal. Returns true if the event has been consumed
   // and should not be processed further.
   bool ProcessArrowKeyTraversal(const ui::KeyEvent& event);
 
+  // Returns true if the |view| is accessibility focusable (checking
+  // IsFocusable() if |keyboard_accessible_| is false on Mac).

[tapted, 2016/05/03 08:08:25]

nit: (this reads a bit funny). Maybe

// Whether |view| is currently focusable per the platform's interpretation of
|keyboard_accesible_|.

[karandeepb, 2016/05/04 01:56:38]

Done.

+  bool IsFocusable(View* view) const;
+
   // Whether arrow key traversal is enabled.
   static bool arrow_key_traversal_enabled_;
 
   // The top-level Widget this FocusManager is associated with.
   Widget* widget_;
 
   // The object which handles an accelerator when |accelerator_manager_| doesn't
   // handle it.
   std::unique_ptr<FocusManagerDelegate> delegate_;
 
@@ skipping 12 matching lines @@
 
   // The reason why the focus most recently changed.
   FocusChangeReason focus_change_reason_;
 
   // The list of registered FocusChange listeners.
   base::ObserverList<FocusChangeListener, true> focus_change_listeners_;
 
   // See description above getter.
   bool is_changing_focus_;
 
+  // This is true if full keyboard accessibility is needed. This causes
+  // IsAccessibilityFocusable() to be checked rather than IsFocusable(). This
+  // can be set depending on platform constraints. FocusSearch uses this in
+  // addition to its own accessibility mode, which handles accessibility at the
+  // FocusTraversable level. Currently only used on Mac, when Full Keyboard
+  // access is enabled.
+  // Default value is false.
+  bool keyboard_accessible_;
+
   DISALLOW_COPY_AND_ASSIGN(FocusManager);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_FOCUS_FOCUS_MANAGER_H_