content/browser/renderer_host/input/touchscreen_tap_suppression_controller.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 CONTENT_BROWSER_RENDERER_HOST_INPUT_TOUCHSCREEN_TAP_SUPPRESSION_CONTROLLER_H_
   6 #define CONTENT_BROWSER_RENDERER_HOST_INPUT_TOUCHSCREEN_TAP_SUPPRESSION_CONTROLLER_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "content/browser/renderer_host/input/gesture_event_filter.h"
  10 #include "content/browser/renderer_host/input/tap_suppression_controller_client.h"
  11
  12 namespace content {
  13
  14 class GestureEventFilter;
  15 class TapSuppressionController;
  16
  17 // Controls the suppression of touchscreen taps immediately following the
  18 // dispatch of a GestureFlingCancel event.
  19 class TouchscreenTapSuppressionController
  20     : public TapSuppressionControllerClient {
  21  public:
  22   explicit TouchscreenTapSuppressionController(GestureEventFilter* gef);
  23   virtual ~TouchscreenTapSuppressionController();
  24
  25   // Should be called on arrival of GestureFlingCancel events.
  26   void GestureFlingCancel();
  27
  28   // Should be called on arrival of ACK for a GestureFlingCancel event.
  29   // |processed| is true if the GestureFlingCancel successfully stopped a fling.
  30   void GestureFlingCancelAck(bool processed);
  31
  32   // Should be called on arrival of GestureTapDown events. Returns true if the
  33   // caller should stop normal handling of the GestureTapDown.
  34   bool ShouldDeferGestureTapDown(const GestureEventWithLatencyInfo& event);
  35
  36   // Should be called on arrival of GestureShowPress events. Returns true if the
  37   // caller should stop normal handling of the GestureShowPress.
  38   bool ShouldDeferGestureShowPress(const GestureEventWithLatencyInfo& event);
  39
  40   // Should be called on arrival of tap-ending gesture events. Returns true if
  41   // the caller should stop normal handling of the GestureTap.
  42   bool ShouldSuppressGestureTapEnd();
  43
  44  private:
  45   // TapSuppressionControllerClient implementation.
  46   virtual int MaxCancelToDownTimeInMs() OVERRIDE;
  47   virtual int MaxTapGapTimeInMs() OVERRIDE;
  48   virtual void DropStashedTapDown() OVERRIDE;
  49   virtual void ForwardStashedTapDown() OVERRIDE;
  50
  51   GestureEventFilter* gesture_event_filter_;
  52
  53   typedef scoped_ptr<GestureEventWithLatencyInfo> ScopedGestureEvent;
  54   ScopedGestureEvent stashed_tap_down_;
  55   ScopedGestureEvent stashed_show_press_;
  56
  57   // The core controller of tap suppression.
  58   scoped_ptr<TapSuppressionController> controller_;
  59
  60   DISALLOW_COPY_AND_ASSIGN(TouchscreenTapSuppressionController);
  61 };
  62
  63 }  // namespace content
  64
  65 #endif  // CONTENT_BROWSER_RENDERER_HOST_INPUT_TOUCHSCREEN_TAP_SUPPRESSION_CONTROLLER_H_