Index: ui/base/accelerators/accelerator_history.h |
diff --git a/ui/base/accelerators/accelerator_history.h b/ui/base/accelerators/accelerator_history.h |
new file mode 100644 |
index 0000000000000000000000000000000000000000..6993ede521f490bd177beef2e51a1e30ecba1460 |
--- /dev/null |
+++ b/ui/base/accelerators/accelerator_history.h |
@@ -0,0 +1,71 @@ |
+// Copyright 2014 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_BASE_ACCELERATORS_ACCELERATOR_HISTORY_H_ |
+#define UI_BASE_ACCELERATORS_ACCELERATOR_HISTORY_H_ |
+ |
+#include "base/memory/singleton.h" |
+#include "ui/base/accelerators/accelerator.h" |
+#include "ui/base/ui_base_export.h" |
+#include "ui/events/event.h" |
+ |
+namespace ui { |
+ |
+// ---------------------------------------------------------------------- |
+// Wraps an accelerator with the time stamp at which it was recorded. |
+// ---------------------------------------------------------------------- |
+struct UI_BASE_EXPORT AcceleratorEvent { |
+ Accelerator accelerator; |
+ base::TimeTicks time_stamp; |
+ |
+ AcceleratorEvent() |
+ : accelerator(), |
+ time_stamp(base::TimeTicks::Now()) { |
+ } |
+ |
+ explicit AcceleratorEvent(const Accelerator& anAccelerator) |
+ : accelerator(anAccelerator), |
+ time_stamp(base::TimeTicks::Now()) { |
+ } |
+}; |
+ |
+// ---------------------------------------------------------------------- |
+// Keeps track of the system-wide current and the most recent previous |
+// key accelerators. |
+// ---------------------------------------------------------------------- |
+class UI_BASE_EXPORT AcceleratorHistory { |
+ public: |
+ static AcceleratorHistory* GetInstance(); |
+ |
+ // Builds and records the current accelerator using the given |event|. |
+ void BuildCurrentAccelerator(const ui::KeyEvent& event); |
+ |
+ // Returns the most recent recorded accelerator. |
+ const AcceleratorEvent& GetCurrentAccelerator() const; |
+ |
+ // Returns the most recent previously recorded accelerator that is different |
+ // than the current. |
+ const AcceleratorEvent& GetPreviousAccelerator() const; |
+ |
+ private: |
+ friend struct DefaultSingletonTraits<AcceleratorHistory>; |
+ |
+ AcceleratorHistory(); |
+ ~AcceleratorHistory(); |
+ |
+ // We are only interested in the most recent 'different' accelerator. If the |
+ // new |event| will result in the same current accelerator then we should |
+ // ignore it. |
+ bool ShouldBuildCurrentAccelerator(const ui::KeyEvent& event, |
+ const int event_modifiers) const; |
+ |
+ AcceleratorEvent current_accelerator_; |
+ AcceleratorEvent previous_accelerator_; |
+ |
+ DISALLOW_COPY_AND_ASSIGN(AcceleratorHistory); |
+}; |
+ |
+}; // namespace ui |
+ |
+#endif // UI_BASE_ACCELERATORS_ACCELERATOR_HISTORY_H_ |