ui/base/user_activity/user_activity_detector.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_BASE_USER_ACTIVITY_USER_ACTIVITY_DETECTOR_H_
   6 #define UI_BASE_USER_ACTIVITY_USER_ACTIVITY_DETECTOR_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/compiler_specific.h"
  10 #include "base/observer_list.h"
  11 #include "base/time/time.h"
  12 #include "ui/base/ui_base_export.h"
  13 #include "ui/events/event_handler.h"
  14
  15 namespace ui {
  16
  17 class UserActivityObserver;
  18
  19 // Watches for input events and notifies observers that the user is active.
  20 class UI_BASE_EXPORT UserActivityDetector : public ui::EventHandler {
  21  public:
  22   // Minimum amount of time between notifications to observers.
  23   static const int kNotifyIntervalMs;
  24
  25   // Amount of time that mouse events should be ignored after notification
  26   // is received that displays' power states are being changed.
  27   static const int kDisplayPowerChangeIgnoreMouseMs;
  28
  29   UserActivityDetector();
  30   ~UserActivityDetector() override;
  31
  32   // Returns the UserActivityDetector instance if one was created.
  33   static UserActivityDetector* Get();
  34
  35   base::TimeTicks last_activity_time() const { return last_activity_time_; }
  36
  37   void set_now_for_test(base::TimeTicks now) { now_for_test_ = now; }
  38
  39   bool HasObserver(const UserActivityObserver* observer) const;
  40   void AddObserver(UserActivityObserver* observer);
  41   void RemoveObserver(UserActivityObserver* observer);
  42
  43   // Called when displays are about to be turned on or off.
  44   void OnDisplayPowerChanging();
  45
  46   // ui::EventHandler implementation.
  47   void OnKeyEvent(ui::KeyEvent* event) override;
  48   void OnMouseEvent(ui::MouseEvent* event) override;
  49   void OnScrollEvent(ui::ScrollEvent* event) override;
  50   void OnTouchEvent(ui::TouchEvent* event) override;
  51   void OnGestureEvent(ui::GestureEvent* event) override;
  52
  53  private:
  54   // Returns |now_for_test_| if set or base::TimeTicks::Now() otherwise.
  55   base::TimeTicks GetCurrentTime() const;
  56
  57   // Updates |last_activity_time_|.  Additionally notifies observers and
  58   // updates |last_observer_notification_time_| if enough time has passed
  59   // since the last notification.
  60   void HandleActivity(const ui::Event* event);
  61
  62   ObserverList<UserActivityObserver> observers_;
  63
  64   // Last time at which user activity was observed.
  65   base::TimeTicks last_activity_time_;
  66
  67   // Last time at which we notified observers that the user was active.
  68   base::TimeTicks last_observer_notification_time_;
  69
  70   // If set, used when the current time is needed.  This can be set by tests to
  71   // simulate the passage of time.
  72   base::TimeTicks now_for_test_;
  73
  74   // If set, mouse events will be ignored until this time is reached. This
  75   // is to avoid reporting mouse events that occur when displays are turned
  76   // on or off as user activity.
  77   base::TimeTicks honor_mouse_events_time_;
  78
  79   DISALLOW_COPY_AND_ASSIGN(UserActivityDetector);
  80 };
  81
  82 }  // namespace ui
  83
  84 #endif  // UI_BASE_USER_ACTIVITY_USER_ACTIVITY_DETECTOR_H_