content/browser/renderer_host/ui_events_helper.h

   1 // Copyright (c) 2012 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_UI_EVENTS_HELPER_H_
   6 #define CONTENT_BROWSER_RENDERER_HOST_UI_EVENTS_HELPER_H_
   7
   8 #include "base/memory/scoped_vector.h"
   9 #include "content/browser/renderer_host/event_with_latency_info.h"
  10 #include "content/common/content_export.h"
  11
  12 namespace blink {
  13 class WebGestureEvent;
  14 class WebTouchEvent;
  15 class WebTouchPoint;
  16 }
  17
  18 namespace ui {
  19 class GestureEvent;
  20 class TouchEvent;
  21 }
  22
  23 namespace content {
  24
  25 enum TouchEventCoordinateSystem {
  26   SCREEN_COORDINATES,
  27   LOCAL_COORDINATES
  28 };
  29
  30 // Creates a list of ui::TouchEvents out of a single WebTouchEvent.
  31 // A WebTouchEvent can contain information about a number of WebTouchPoints,
  32 // whereas a ui::TouchEvent contains information about a single touch-point. So
  33 // it is possible to create more than one ui::TouchEvents out of a single
  34 // WebTouchEvent. All the ui::TouchEvent in the list will carry the same
  35 // LatencyInfo the WebTouchEvent carries.
  36 // |coordinate_system| specifies which fields to use for the co-ordinates,
  37 // WebTouchPoint.position or WebTouchPoint.screenPosition.  Is's up to the
  38 // caller to do any co-ordinate system mapping (typically to get them into
  39 // the Aura EventDispatcher co-ordinate system).
  40 CONTENT_EXPORT bool MakeUITouchEventsFromWebTouchEvents(
  41     const TouchEventWithLatencyInfo& touch,
  42     ScopedVector<ui::TouchEvent>* list,
  43     TouchEventCoordinateSystem coordinate_system);
  44
  45 // Creates a WebGestureEvent from a ui::GestureEvent. Note that it does not
  46 // populate the event coordinates (i.e. |x|, |y|, |globalX|, and |globalY|). So
  47 // the caller must populate these fields.
  48 blink::WebGestureEvent MakeWebGestureEventFromUIEvent(
  49     const ui::GestureEvent& event);
  50
  51 }  // namespace content
  52
  53 #endif  // CONTENT_BROWSER_RENDERER_HOST_UI_EVENTS_HELPER_H_