Suppress touchscreen tap immediately after a GestureFlingCancel

content/browser/renderer_host/touchscreen_tap_suppression_controller.h

+// Copyright (c) 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.
+
+#ifndef CONTENT_BROWSER_RENDERER_HOST_TOUCHSCREEN_TAP_SUPPRESSION_CONTROLLER_H_
+#define CONTENT_BROWSER_RENDERER_HOST_TOUCHSCREEN_TAP_SUPPRESSION_CONTROLLER_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "content/browser/renderer_host/tap_suppression_controller_client.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebInputEvent.h"
+
+namespace content {
+
+class GestureEventFilter;
+class TapSuppressionController;
+
+// Controls the suppression of touchscreen taps immediately following the
+// dispatch of a GestureFlingCancel event.
+class TouchscreenTapSuppressionController
+    : public TapSuppressionControllerClient {
+ public:
+  explicit TouchscreenTapSuppressionController(GestureEventFilter* gef);
+  virtual ~TouchscreenTapSuppressionController();
+
+  // Should be called on arrival of GestureFlingCancel events.
+  void GestureFlingCancel();
+
+  // Should be called on arrival of ACK for a GestureFlingCancel event.
+  // |processed| is true if the GestureFlingCancel successfully stopped a fling.
+  void GestureFlingCancelAck(bool processed);
+
+  // Should be called on arrival of GestureTapDown events. Returns true if the
+  // caller should stop normal handling of the GestureTapDown. In this case, the
+  // caller is responsible for saving the event for later use, if needed.
+  bool ShouldDeferGestureTapDown(const WebKit::WebGestureEvent& event);
+
+  // Should be called on arrival of GestureTap events. Returns true if the
+  // caller should stop normal handling of the GestureTap.
+  bool ShouldSuppressGestureTap();
+
+  // Should be called on arrival of GestureTapCancel events. Returns true if the
+  // caller should stop normal handling of the GestureTapCancel.
+  bool ShouldSuppressGestureTapCancel();
+
+ private:
+  // TapSuppressionControllerClient implementation.
+  virtual int MaxCancelToDownTimeInMs() OVERRIDE;
+  virtual int MaxTapGapTimeInMs() OVERRIDE;
+  virtual void DropStashedTapDown() OVERRIDE;
+  virtual void ForwardStashedTapDownForDeferral() OVERRIDE;
+  virtual void ForwardStashedTapDownSkipDeferral() OVERRIDE;
+
+  GestureEventFilter* gesture_event_filter_;
+  WebKit::WebGestureEvent stashed_tap_down_;
+
+  // The core controller of tap suppression.
+  scoped_ptr<TapSuppressionController> controller_;
+
+  DISALLOW_COPY_AND_ASSIGN(TouchscreenTapSuppressionController);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_RENDERER_HOST_TOUCHSCREEN_TAP_SUPPRESSION_CONTROLLER_H_