1 // Copyright 2014 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_COMMON_INPUT_WEB_TOUCH_EVENT_TRAITS_H_ 6 #define CONTENT_COMMON_INPUT_WEB_TOUCH_EVENT_TRAITS_H_ 7 8 #include "base/basictypes.h" 9 #include "content/common/input/scoped_web_input_event.h" 10 #include "third_party/WebKit/public/web/WebInputEvent.h" 11 12 namespace content { 13 14 // Utility class for performing operations on and with WebTouchEvents. 15 class CONTENT_EXPORT WebTouchEventTraits { 16 public: 17 // Returns whether all touches in the event have the specified state. 18 static bool AllTouchPointsHaveState(const blink::WebTouchEvent& event, 19 blink::WebTouchPoint::State state); 20 21 // Returns whether this event represents a transition from no active 22 // touches to some active touches (the start of a new "touch sequence"). 23 static bool IsTouchSequenceStart(const blink::WebTouchEvent& event); 24 25 // Returns whether this event represents a transition from active 26 // touches to no active touches (the end of a "touch sequence"). 27 static bool IsTouchSequenceEnd(const blink::WebTouchEvent& event); 28 29 // Sets the type of |event| to |type|, resetting any other type-specific 30 // properties and updating the timestamp. 31 static void ResetType(blink::WebInputEvent::Type type, 32 double timestamp_sec, 33 blink::WebTouchEvent* event); 34 35 // Like ResetType but also resets the state of all active touches 36 // to match the event type. This is particularly useful, for example, 37 // in sending a touchcancel for all active touches. 38 static void ResetTypeAndTouchStates(blink::WebInputEvent::Type type, 39 double timestamp_sec, 40 blink::WebTouchEvent* event); 41 }; 42 43 } // namespace content 44 45 #endif // CONTENT_COMMON_INPUT_WEB_TOUCH_EVENT_TRAITS_H_ 46