It is time.

ui/views/focus/focus_search.h

-// Copyright (c) 2011 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_SEARCH_H_
-#define UI_VIEWS_FOCUS_FOCUS_SEARCH_H_
-
-#include "ui/views/view.h"
-
-namespace views {
-
-class FocusTraversable;
-
-// FocusSearch is an object that implements the algorithm to find the
-// next view to focus.
-class VIEWS_EXPORT FocusSearch {
- public:
-  // The direction in which the focus traversal is going.
-  // TODO (jcampan): add support for lateral (left, right) focus traversal. The
-  // goal is to switch to focusable views on the same level when using the arrow
-  // keys (ala Windows: in a dialog box, arrow keys typically move between the
-  // dialog OK, Cancel buttons).
-  enum Direction {
-    UP = 0,
-    DOWN
-  };
-
-  // Constructor.
-  // - |root| is the root of the view hierarchy to traverse. Focus will be
-  //   trapped inside.
-  // - |cycle| should be true if you want FindNextFocusableView to cycle back
-  //           to the first view within this root when the traversal reaches
-  //           the end. If this is true, then if you pass a valid starting
-  //           view to FindNextFocusableView you will always get a valid view
-  //           out, even if it's the same view.
-  // - |accessibility_mode| should be true if full keyboard accessibility is
-  //   needed and you want to check IsAccessibilityFocusable(), rather than
-  //   IsFocusable().
-  FocusSearch(View* root, bool cycle, bool accessibility_mode);
-  virtual ~FocusSearch() {}
-
-  // Finds the next view that should be focused and returns it. If a
-  // FocusTraversable is found while searching for the focusable view,
-  // returns NULL and sets |focus_traversable| to the FocusTraversable
-  // and |focus_traversable_view| to the view associated with the
-  // FocusTraversable.
-  //
-  // Return NULL if the end of the focus loop is reached, unless this object
-  // was initialized with |cycle|=true, in which case it goes back to the
-  // beginning when it reaches the end of the traversal.
-  // - |starting_view| is the view that should be used as the starting point
-  //   when looking for the previous/next view. It may be NULL (in which case
-  //   the first/last view should be used depending if normal/reverse).
-  // - |reverse| whether we should find the next (reverse is false) or the
-  //   previous (reverse is true) view.
-  // - |direction| specifies whether we are traversing down (meaning we should
-  //   look into child views) or traversing up (don't look at child views).
-  // - |check_starting_view| is true if starting_view may obtain the next focus.
-  // - |focus_traversable| is set to the focus traversable that should be
-  //   traversed if one is found (in which case the call returns NULL).
-  // - |focus_traversable_view| is set to the view associated with the
-  //   FocusTraversable set in the previous parameter (it is used as the
-  //   starting view when looking for the next focusable view).
-  virtual View* FindNextFocusableView(View* starting_view,
-                                      bool reverse,
-                                      Direction direction,
-                                      bool check_starting_view,
-                                      FocusTraversable** focus_traversable,
-                                      View** focus_traversable_view);
-
- protected:
-  // Get the parent, but stay within the root. Returns NULL if asked for
-  // the parent of |root_|. Subclasses can override this if they need custom
-  // focus search behavior.
-  virtual View* GetParent(View* v);
-
-  // Returns true if |v| is contained within the hierarchy rooted at |root|.
-  // Subclasses can override this if they need custom focus search behavior.
-  virtual bool Contains(View* root, const View* v);
-
-  View* root() const { return root_; }
-
- private:
-  // Convenience method that returns true if a view is focusable and does not
-  // belong to the specified group.
-  bool IsViewFocusableCandidate(View* v, int skip_group_id);
-
-  // Convenience method; returns true if a view is not NULL and is focusable
-  // (checking IsAccessibilityFocusable() if |accessibility_mode_| is true).
-  bool IsFocusable(View* v);
-
-  // Returns the view selected for the group of the selected view. If the view
-  // does not belong to a group or if no view is selected in the group, the
-  // specified view is returned.
-  View* FindSelectedViewForGroup(View* view);
-
-  // Returns the next focusable view or view containing a FocusTraversable
-  // (NULL if none was found), starting at the starting_view.
-  // |check_starting_view|, |can_go_up| and |can_go_down| controls the
-  // traversal of the views hierarchy. |skip_group_id| specifies a group_id,
-  // -1 means no group. All views from a group are traversed in one pass.
-  View* FindNextFocusableViewImpl(View* starting_view,
-                                  bool check_starting_view,
-                                  bool can_go_up,
-                                  bool can_go_down,
-                                  int skip_group_id,
-                                  FocusTraversable** focus_traversable,
-                                  View** focus_traversable_view);
-
-  // Same as FindNextFocusableViewImpl but returns the previous focusable view.
-  View* FindPreviousFocusableViewImpl(View* starting_view,
-                                      bool check_starting_view,
-                                      bool can_go_up,
-                                      bool can_go_down,
-                                      int skip_group_id,
-                                      FocusTraversable** focus_traversable,
-                                      View** focus_traversable_view);
-
-  View* root_;
-  bool cycle_;
-  bool accessibility_mode_;
-
-  DISALLOW_COPY_AND_ASSIGN(FocusSearch);
-};
-
-}  // namespace views
-
-#endif  // UI_VIEWS_FOCUS_FOCUS_SEARCH_H_