It is time.

ui/wm/core/focus_controller.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_WM_CORE_FOCUS_CONTROLLER_H_
-#define UI_WM_CORE_FOCUS_CONTROLLER_H_
-
-#include "base/compiler_specific.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/observer_list.h"
-#include "base/scoped_observer.h"
-#include "ui/aura/client/focus_client.h"
-#include "ui/aura/window_observer.h"
-#include "ui/events/event_handler.h"
-#include "ui/wm/public/activation_client.h"
-#include "ui/wm/wm_export.h"
-
-namespace wm {
-
-class FocusRules;
-
-// FocusController handles focus and activation changes for an environment
-// encompassing one or more RootWindows. Within an environment there can be
-// only one focused and one active window at a time. When focus or activation
-// changes notifications are sent using the
-// aura::client::Focus/ActivationChangeObserver interfaces.
-// Changes to focus and activation can be from three sources:
-// . the Aura Client API (implemented here in aura::client::ActivationClient).
-//   (The FocusController must be set as the ActivationClient implementation
-//    for all RootWindows).
-// . input events (implemented here in ui::EventHandler).
-//   (The FocusController must be registered as a pre-target handler for
-//    the applicable environment owner, either a RootWindow or another type).
-// . Window disposition changes (implemented here in aura::WindowObserver).
-//   (The FocusController registers itself as an observer of the active and
-//    focused windows).
-class WM_EXPORT FocusController : public aura::client::ActivationClient,
-                                  public aura::client::FocusClient,
-                                  public ui::EventHandler,
-                                  public aura::WindowObserver {
- public:
-  // |rules| cannot be NULL.
-  explicit FocusController(FocusRules* rules);
-  virtual ~FocusController();
-
- private:
-  // Overridden from aura::client::ActivationClient:
-  virtual void AddObserver(
-      aura::client::ActivationChangeObserver* observer) override;
-  virtual void RemoveObserver(
-      aura::client::ActivationChangeObserver* observer) override;
-  virtual void ActivateWindow(aura::Window* window) override;
-  virtual void DeactivateWindow(aura::Window* window) override;
-  virtual aura::Window* GetActiveWindow() override;
-  virtual aura::Window* GetActivatableWindow(aura::Window* window) override;
-  virtual aura::Window* GetToplevelWindow(aura::Window* window) override;
-  virtual bool CanActivateWindow(aura::Window* window) const override;
-
-  // Overridden from aura::client::FocusClient:
-  virtual void AddObserver(
-      aura::client::FocusChangeObserver* observer) override;
-  virtual void RemoveObserver(
-      aura::client::FocusChangeObserver* observer) override;
-  virtual void FocusWindow(aura::Window* window) override;
-  virtual void ResetFocusWithinActiveWindow(aura::Window* window) override;
-  virtual aura::Window* GetFocusedWindow() override;
-
-  // Overridden from ui::EventHandler:
-  virtual void OnKeyEvent(ui::KeyEvent* event) override;
-  virtual void OnMouseEvent(ui::MouseEvent* event) override;
-  virtual void OnScrollEvent(ui::ScrollEvent* event) override;
-  virtual void OnTouchEvent(ui::TouchEvent* event) override;
-  virtual void OnGestureEvent(ui::GestureEvent* event) override;
-
-  // Overridden from aura::WindowObserver:
-  virtual void OnWindowVisibilityChanged(aura::Window* window,
-                                         bool visible) override;
-  virtual void OnWindowDestroying(aura::Window* window) override;
-  virtual void OnWindowHierarchyChanging(
-      const HierarchyChangeParams& params) override;
-  virtual void OnWindowHierarchyChanged(
-      const HierarchyChangeParams& params) override;
-
-  // Internal implementation that sets the focused window, fires events etc.
-  // This function must be called with a valid focusable window.
-  void SetFocusedWindow(aura::Window* window);
-
-  // Internal implementation that sets the active window, fires events etc.
-  // This function must be called with a valid |activatable_window|.
-  // |requested window| refers to the window that was passed in to an external
-  // request (e.g. FocusWindow or ActivateWindow). It may be NULL, e.g. if
-  // SetActiveWindow was not called by an external request. |activatable_window|
-  // refers to the actual window to be activated, which may be different.
-  void SetActiveWindow(aura::Window* requested_window,
-                       aura::Window* activatable_window);
-
-  // Called when a window's disposition changed such that it and its hierarchy
-  // are no longer focusable/activatable. |next| is a valid window that is used
-  // as a starting point for finding a window to focus next based on rules.
-  void WindowLostFocusFromDispositionChange(aura::Window* window,
-                                            aura::Window* next);
-
-  // Called when an attempt is made to focus or activate a window via an input
-  // event targeted at that window. Rules determine the best focusable window
-  // for the input window.
-  void WindowFocusedFromInputEvent(aura::Window* window);
-
-  aura::Window* active_window_;
-  aura::Window* focused_window_;
-
-  bool updating_focus_;
-  bool updating_activation_;
-
-  scoped_ptr<FocusRules> rules_;
-
-  ObserverList<aura::client::ActivationChangeObserver> activation_observers_;
-  ObserverList<aura::client::FocusChangeObserver> focus_observers_;
-
-  ScopedObserver<aura::Window, aura::WindowObserver> observer_manager_;
-
-  DISALLOW_COPY_AND_ASSIGN(FocusController);
-};
-
-}  // namespace wm
-
-#endif  // UI_WM_CORE_FOCUS_CONTROLLER_H_