ash/keyboard_uma_event_filter.h

   1 // Copyright 2013 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 ASH_KEYBOARD_UMA_EVENT_FILTER_H_
   6 #define ASH_KEYBOARD_UMA_EVENT_FILTER_H_
   7
   8 #include "base/compiler_specific.h"
   9 #include "base/time/time.h"
  10 #include "ui/events/event_handler.h"
  11
  12 namespace ash {
  13
  14 // EventFilter for tracking keyboard-related metrics, which intercepts events
  15 // before they are processed by the usual path and logs metrics about the
  16 // events.
  17 class KeyboardUMAEventFilter : public ui::EventHandler {
  18  public:
  19   KeyboardUMAEventFilter();
  20   ~KeyboardUMAEventFilter() override;
  21
  22   // ui::EventHandler overrides:
  23   void OnKeyEvent(ui::KeyEvent* event) override;
  24
  25  private:
  26   // The timestamp of the last character keystroke.
  27   base::TimeDelta last_keystroke_time_;
  28
  29   DISALLOW_COPY_AND_ASSIGN(KeyboardUMAEventFilter);
  30 };
  31
  32 }  // namespace ash
  33
  34 #endif  // ASH_KEYBOARD_UMA_EVENT_FILTER_H_