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 UI_EVENTS_EVENT_UTILS_H_ 6 #define UI_EVENTS_EVENT_UTILS_H_ 7 8 #include "base/event_types.h" 9 #include "ui/events/event_constants.h" 10 #include "ui/events/keycodes/keyboard_codes.h" 11 #include "ui/gfx/native_widget_types.h" 12 #include "ui/events/events_export.h" 13 14 #if defined(OS_WIN) 15 #include <windows.h> 16 #endif 17 18 namespace gfx { 19 class Point; 20 class Vector2d; 21 } 22 23 namespace base { 24 class TimeDelta; 25 } 26 27 namespace ui { 28 29 class Event; 30 31 // Updates the list of devices for cached properties. 32 EVENTS_EXPORT void UpdateDeviceList(); 33 34 // Get the EventType from a native event. 35 EVENTS_EXPORT EventType EventTypeFromNative( 36 const base::NativeEvent& native_event); 37 38 // Get the EventFlags from a native event. 39 EVENTS_EXPORT int EventFlagsFromNative(const base::NativeEvent& native_event); 40 41 // Get the timestamp from a native event. 42 EVENTS_EXPORT base::TimeDelta EventTimeFromNative( 43 const base::NativeEvent& native_event); 44 45 // Create a timestamp based on the current time. 46 EVENTS_EXPORT base::TimeDelta EventTimeForNow(); 47 48 // Get the location from a native event. The coordinate system of the resultant 49 // |Point| has the origin at top-left of the "root window". The nature of 50 // this "root window" and how it maps to platform-specific drawing surfaces is 51 // defined in ui/aura/root_window.* and ui/aura/root_window_host*. 52 EVENTS_EXPORT gfx::Point EventLocationFromNative( 53 const base::NativeEvent& native_event); 54 55 // Gets the location in native system coordinate space. 56 EVENTS_EXPORT gfx::Point EventSystemLocationFromNative( 57 const base::NativeEvent& native_event); 58 59 #if defined(USE_X11) 60 // Returns the 'real' button for an event. The button reported in slave events 61 // does not take into account any remapping (e.g. using xmodmap), while the 62 // button reported in master events do. This is a utility function to always 63 // return the mapped button. 64 EVENTS_EXPORT int EventButtonFromNative(const base::NativeEvent& native_event); 65 #endif 66 67 // Returns the KeyboardCode from a native event. 68 EVENTS_EXPORT KeyboardCode KeyboardCodeFromNative( 69 const base::NativeEvent& native_event); 70 71 // Returns the DOM KeyboardEvent code (physical location in the 72 // keyboard) from a native event. The ownership of the return value 73 // is NOT trasferred to the caller. 74 EVENTS_EXPORT const char* CodeFromNative( 75 const base::NativeEvent& native_event); 76 77 // Returns true if the message is a mouse event. 78 EVENTS_EXPORT bool IsMouseEvent(const base::NativeEvent& native_event); 79 80 // Returns the flags of the button that changed during a press/release. 81 EVENTS_EXPORT int GetChangedMouseButtonFlagsFromNative( 82 const base::NativeEvent& native_event); 83 84 // Gets the mouse wheel offsets from a native event. 85 EVENTS_EXPORT gfx::Vector2d GetMouseWheelOffset( 86 const base::NativeEvent& native_event); 87 88 // Gets the touch id from a native event. 89 EVENTS_EXPORT int GetTouchId(const base::NativeEvent& native_event); 90 91 // Clear the touch id from bookkeeping if it is a release/cancel event. 92 EVENTS_EXPORT void ClearTouchIdIfReleased( 93 const base::NativeEvent& native_event); 94 95 // Gets the radius along the X/Y axis from a native event. Default is 1.0. 96 EVENTS_EXPORT float GetTouchRadiusX(const base::NativeEvent& native_event); 97 EVENTS_EXPORT float GetTouchRadiusY(const base::NativeEvent& native_event); 98 99 // Gets the angle of the major axis away from the X axis. Default is 0.0. 100 EVENTS_EXPORT float GetTouchAngle(const base::NativeEvent& native_event); 101 102 // Gets the force from a native_event. Normalized to be [0, 1]. Default is 0.0. 103 EVENTS_EXPORT float GetTouchForce(const base::NativeEvent& native_event); 104 105 // Gets the fling velocity from a native event. is_cancel is set to true if 106 // this was a tap down, intended to stop an ongoing fling. 107 EVENTS_EXPORT bool GetFlingData(const base::NativeEvent& native_event, 108 float* vx, 109 float* vy, 110 float* vx_ordinal, 111 float* vy_ordinal, 112 bool* is_cancel); 113 114 // Returns whether this is a scroll event and optionally gets the amount to be 115 // scrolled. |x_offset|, |y_offset| and |finger_count| can be NULL. 116 EVENTS_EXPORT bool GetScrollOffsets(const base::NativeEvent& native_event, 117 float* x_offset, 118 float* y_offset, 119 float* x_offset_ordinal, 120 float* y_offset_ordinal, 121 int* finger_count); 122 123 EVENTS_EXPORT bool GetGestureTimes(const base::NativeEvent& native_event, 124 double* start_time, 125 double* end_time); 126 127 // Enable/disable natural scrolling for touchpads. 128 EVENTS_EXPORT void SetNaturalScroll(bool enabled); 129 130 // In natural scrolling enabled for touchpads? 131 EVENTS_EXPORT bool IsNaturalScrollEnabled(); 132 133 // Returns whether natural scrolling should be used for touchpad. 134 EVENTS_EXPORT bool ShouldDefaultToNaturalScroll(); 135 136 // Was this event generated by a touchpad device? 137 // The caller is responsible for ensuring that this is a mouse/touchpad event 138 // before calling this function. 139 EVENTS_EXPORT bool IsTouchpadEvent(const base::NativeEvent& event); 140 141 // Returns true if event is noop. 142 EVENTS_EXPORT bool IsNoopEvent(const base::NativeEvent& event); 143 144 // Creates and returns no-op event. 145 EVENTS_EXPORT base::NativeEvent CreateNoopEvent(); 146 147 #if defined(OS_WIN) 148 EVENTS_EXPORT int GetModifiersFromACCEL(const ACCEL& accel); 149 EVENTS_EXPORT int GetModifiersFromKeyState(); 150 151 // Returns true if |message| identifies a mouse event that was generated as the 152 // result of a touch event. 153 EVENTS_EXPORT bool IsMouseEventFromTouch(UINT message); 154 155 // Converts scan code and lParam each other. The scan code 156 // representing an extended key contains 0xE000 bits. 157 EVENTS_EXPORT uint16 GetScanCodeFromLParam(LPARAM lParam); 158 EVENTS_EXPORT LPARAM GetLParamFromScanCode(uint16 scan_code); 159 #endif 160 161 // Returns true if default post-target handling was canceled for |event| after 162 // its dispatch to its target. 163 EVENTS_EXPORT bool EventCanceledDefaultHandling(const Event& event); 164 165 // Registers a custom event type. 166 EVENTS_EXPORT int RegisterCustomEventType(); 167 168 } // namespace ui 169 170 #endif // UI_EVENTS_EVENT_UTILS_H_ 171