blob: 4c27021d37ae4a28a9dc3de8529d5fe7526a4dbe [file] [log] [blame]
// Copyright 2013 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.
#include <stddef.h>
#include <memory>
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/synchronization/lock.h"
#include "media/base/media_export.h"
namespace base {
class SingleThreadTaskRunner;
} // namespace base
namespace media {
// Monitors and notifies about keyboard events.
// Thread safe.
class MEDIA_EXPORT UserInputMonitor {
virtual ~UserInputMonitor();
// Creates a platform-specific instance of UserInputMonitor.
// |io_task_runner| is the task runner for an IO thread.
// |ui_task_runner| is the task runner for a UI thread.
static std::unique_ptr<UserInputMonitor> Create(
const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
const scoped_refptr<base::SingleThreadTaskRunner>& ui_task_runner);
// A caller must call EnableKeyPressMonitoring and
// DisableKeyPressMonitoring in pair.
void EnableKeyPressMonitoring();
void DisableKeyPressMonitoring();
// Returns the number of keypresses. The starting point from when it is
// counted is not guaranteed, but consistent within the pair of calls of
// EnableKeyPressMonitoring and DisableKeyPressMonitoring. So a caller can
// use the difference between the values returned at two times to get the
// number of keypresses happened within that time period, but should not make
// any assumption on the initial value.
virtual size_t GetKeyPressCount() const = 0;
virtual void StartKeyboardMonitoring() = 0;
virtual void StopKeyboardMonitoring() = 0;
base::Lock lock_;
size_t key_press_counter_references_;
} // namespace media