| // Copyright 2016 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 THIRD_PARTY_BLINK_PUBLIC_COMMON_INPUT_WEB_MOUSE_WHEEL_EVENT_H_ |
| #define THIRD_PARTY_BLINK_PUBLIC_COMMON_INPUT_WEB_MOUSE_WHEEL_EVENT_H_ |
| |
| #include "third_party/blink/public/common/input/web_mouse_event.h" |
| #include "ui/events/types/scroll_types.h" |
| |
| namespace blink { |
| |
| // WebMouseWheelEvent --------------------------------------------------------- |
| |
| class BLINK_COMMON_EXPORT WebMouseWheelEvent : public WebMouseEvent { |
| public: |
| enum Phase { |
| // No phase information is avaiable. |
| kPhaseNone = 0, |
| // This wheel event is the beginning of a scrolling sequence. |
| kPhaseBegan = 1 << 0, |
| // Shows that scrolling is ongoing but the scroll delta for this wheel event |
| // is zero. |
| kPhaseStationary = 1 << 1, |
| // Shows that a scroll is ongoing and the scroll delta for this wheel event |
| // is non-zero. |
| kPhaseChanged = 1 << 2, |
| // This wheel event is the last event of a scrolling sequence. |
| kPhaseEnded = 1 << 3, |
| // A wheel event with phase cancelled shows that the scrolling sequence is |
| // cancelled. |
| kPhaseCancelled = 1 << 4, |
| // A wheel event with phase may begin shows that a scrolling sequence may |
| // start. |
| kPhaseMayBegin = 1 << 5, |
| // A wheel event with momentum phase blocked shows that a scrolling sequence |
| // will not be followed by a momentum fling. This should only ever be set on |
| // the momentum phase of an event. |
| kPhaseBlocked = 1 << 6, |
| }; |
| |
| // A hint at the outcome of a wheel event should it not get canceled. |
| enum class EventAction : int { |
| // When the wheel event would result in page zoom, |
| kPageZoom = 0, |
| // When the wheel event would scroll but the direction is not (known to be) |
| // fixed to a certain axis, |
| kScroll, |
| // When the wheel event would scroll along X axis, |
| kScrollHorizontal, |
| // When the wheel event would scroll along Y axis, |
| kScrollVertical |
| }; |
| |
| float delta_x = 0.0f; |
| float delta_y = 0.0f; |
| float wheel_ticks_x = 0.0f; |
| float wheel_ticks_y = 0.0f; |
| |
| float acceleration_ratio_x = 1.0f; |
| float acceleration_ratio_y = 1.0f; |
| |
| Phase phase = kPhaseNone; |
| Phase momentum_phase = kPhaseNone; |
| |
| RailsMode rails_mode = kRailsModeFree; |
| |
| // Whether the event is blocking, non-blocking, all event |
| // listeners were passive or was forced to be non-blocking. |
| DispatchType dispatch_type = DispatchType::kBlocking; |
| |
| // The expected result of this wheel event (if not canceled). |
| EventAction event_action = EventAction::kPageZoom; |
| |
| // True when phase information is added in mouse_wheel_phase_handler based |
| // on its timer. |
| bool has_synthetic_phase = false; |
| |
| // The units of delta_x and delta_y. Currently only supports |
| // kScrollByPrecisePixel, kScrollByPixel, and kScrollByPage, as they are |
| // the only values expected after converting an OS event to a |
| // WebMouseWheelEvent. |
| ui::ScrollGranularity delta_units = ui::ScrollGranularity::kScrollByPixel; |
| |
| WebMouseWheelEvent(Type type, int modifiers, base::TimeTicks time_stamp) |
| : WebMouseEvent(type, modifiers, time_stamp, kMousePointerId) {} |
| |
| WebMouseWheelEvent() : WebMouseEvent(kMousePointerId) {} |
| |
| float DeltaXInRootFrame() const; |
| float DeltaYInRootFrame() const; |
| |
| // Sets any scaled values to be their computed values and sets |frame_scale_| |
| // back to 1 and |frame_translate_| X and Y coordinates back to 0. |
| WebMouseWheelEvent FlattenTransform() const; |
| |
| bool IsCancelable() const { return dispatch_type == DispatchType::kBlocking; } |
| |
| std::unique_ptr<WebInputEvent> Clone() const override; |
| bool CanCoalesce(const WebInputEvent& event) const override; |
| void Coalesce(const WebInputEvent& event) override; |
| |
| // Return the platform specific default event action given the mouse wheel |
| // event. Can be used to determine the appropriate value for |event_action|. |
| static EventAction GetPlatformSpecificDefaultEventAction( |
| const WebMouseWheelEvent& event); |
| |
| private: |
| bool HaveConsistentPhase(const WebMouseWheelEvent& event) const; |
| }; |
| |
| } // namespace blink |
| |
| #endif // THIRD_PARTY_BLINK_PUBLIC_COMMON_INPUT_WEB_MOUSE_WHEEL_EVENT_H_ |