ui/events/event_utils.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 UI_EVENTS_EVENT_UTILS_H_
   6 #define UI_EVENTS_EVENT_UTILS_H_
   7
   8 #include "base/event_types.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "ui/events/event_constants.h"
  11 #include "ui/events/keycodes/keyboard_codes.h"
  12 #include "ui/gfx/display.h"
  13 #include "ui/gfx/native_widget_types.h"
  14 #include "ui/events/events_export.h"
  15
  16 #if defined(OS_WIN)
  17 #include <windows.h>
  18 #endif
  19
  20 namespace gfx {
  21 class Point;
  22 class Vector2d;
  23 }
  24
  25 namespace base {
  26 class TimeDelta;
  27 }
  28
  29 namespace ui {
  30
  31 class Event;
  32
  33 // Updates the list of devices for cached properties.
  34 EVENTS_EXPORT void UpdateDeviceList();
  35
  36 // Returns a ui::Event wrapping a native event. Ownership of the returned value
  37 // is transferred to the caller.
  38 EVENTS_EXPORT scoped_ptr<Event> EventFromNative(
  39     const base::NativeEvent& native_event);
  40
  41 // Get the EventType from a native event.
  42 EVENTS_EXPORT EventType EventTypeFromNative(
  43     const base::NativeEvent& native_event);
  44
  45 // Get the EventFlags from a native event.
  46 EVENTS_EXPORT int EventFlagsFromNative(const base::NativeEvent& native_event);
  47
  48 // Get the timestamp from a native event.
  49 EVENTS_EXPORT base::TimeDelta EventTimeFromNative(
  50     const base::NativeEvent& native_event);
  51
  52 // Create a timestamp based on the current time.
  53 EVENTS_EXPORT base::TimeDelta EventTimeForNow();
  54
  55 // Get the location from a native event.  The coordinate system of the resultant
  56 // |Point| has the origin at top-left of the "root window".  The nature of
  57 // this "root window" and how it maps to platform-specific drawing surfaces is
  58 // defined in ui/aura/root_window.* and ui/aura/window_tree_host*.
  59 // TODO(tdresser): Return gfx::PointF here. See crbug.com/337827.
  60 EVENTS_EXPORT gfx::Point EventLocationFromNative(
  61     const base::NativeEvent& native_event);
  62
  63 // Gets the location in native system coordinate space.
  64 EVENTS_EXPORT gfx::Point EventSystemLocationFromNative(
  65     const base::NativeEvent& native_event);
  66
  67 #if defined(USE_X11)
  68 // Returns the 'real' button for an event. The button reported in slave events
  69 // does not take into account any remapping (e.g. using xmodmap), while the
  70 // button reported in master events do. This is a utility function to always
  71 // return the mapped button.
  72 EVENTS_EXPORT int EventButtonFromNative(const base::NativeEvent& native_event);
  73 #endif
  74
  75 // Returns the KeyboardCode from a native event.
  76 EVENTS_EXPORT KeyboardCode KeyboardCodeFromNative(
  77     const base::NativeEvent& native_event);
  78
  79 // Returns the DOM KeyboardEvent code (physical location in the
  80 // keyboard) from a native event.  The ownership of the return value
  81 // is NOT trasferred to the caller.
  82 EVENTS_EXPORT const char* CodeFromNative(
  83     const base::NativeEvent& native_event);
  84
  85 // Returns the platform related key code. For X11, it is xksym value.
  86 EVENTS_EXPORT uint32 PlatformKeycodeFromNative(
  87     const base::NativeEvent& native_event);
  88
  89 // Returns the flags of the button that changed during a press/release.
  90 EVENTS_EXPORT int GetChangedMouseButtonFlagsFromNative(
  91     const base::NativeEvent& native_event);
  92
  93 // Gets the mouse wheel offsets from a native event.
  94 EVENTS_EXPORT gfx::Vector2d GetMouseWheelOffset(
  95     const base::NativeEvent& native_event);
  96
  97 // Returns a copy of |native_event|. Depending on the platform, this copy may
  98 // need to be deleted with ReleaseCopiedNativeEvent().
  99 base::NativeEvent CopyNativeEvent(
 100     const base::NativeEvent& native_event);
 101
 102 // Delete a |native_event| previously created by CopyNativeEvent().
 103 void ReleaseCopiedNativeEvent(
 104     const base::NativeEvent& native_event);
 105
 106 // Gets the touch id from a native event.
 107 EVENTS_EXPORT int GetTouchId(const base::NativeEvent& native_event);
 108
 109 // Clear the touch id from bookkeeping if it is a release/cancel event.
 110 EVENTS_EXPORT void ClearTouchIdIfReleased(
 111     const base::NativeEvent& native_event);
 112
 113 // Gets the radius along the X/Y axis from a native event. Default is 1.0.
 114 EVENTS_EXPORT float GetTouchRadiusX(const base::NativeEvent& native_event);
 115 EVENTS_EXPORT float GetTouchRadiusY(const base::NativeEvent& native_event);
 116
 117 // Gets the angle of the major axis away from the X axis. Default is 0.0.
 118 EVENTS_EXPORT float GetTouchAngle(const base::NativeEvent& native_event);
 119
 120 // Gets the force from a native_event. Normalized to be [0, 1]. Default is 0.0.
 121 EVENTS_EXPORT float GetTouchForce(const base::NativeEvent& native_event);
 122
 123 // Gets the fling velocity from a native event. is_cancel is set to true if
 124 // this was a tap down, intended to stop an ongoing fling.
 125 EVENTS_EXPORT bool GetFlingData(const base::NativeEvent& native_event,
 126                             float* vx,
 127                             float* vy,
 128                             float* vx_ordinal,
 129                             float* vy_ordinal,
 130                             bool* is_cancel);
 131
 132 // Returns whether this is a scroll event and optionally gets the amount to be
 133 // scrolled. |x_offset|, |y_offset| and |finger_count| can be NULL.
 134 EVENTS_EXPORT bool GetScrollOffsets(const base::NativeEvent& native_event,
 135                                 float* x_offset,
 136                                 float* y_offset,
 137                                 float* x_offset_ordinal,
 138                                 float* y_offset_ordinal,
 139                                 int* finger_count);
 140
 141 EVENTS_EXPORT bool GetGestureTimes(const base::NativeEvent& native_event,
 142                                double* start_time,
 143                                double* end_time);
 144
 145 // Returns whether natural scrolling should be used for touchpad.
 146 EVENTS_EXPORT bool ShouldDefaultToNaturalScroll();
 147
 148 // Returns whether or not the internal display produces touch events.
 149 EVENTS_EXPORT gfx::Display::TouchSupport GetInternalDisplayTouchSupport();
 150
 151 #if defined(OS_WIN)
 152 EVENTS_EXPORT int GetModifiersFromACCEL(const ACCEL& accel);
 153 EVENTS_EXPORT int GetModifiersFromKeyState();
 154
 155 // Returns true if |message| identifies a mouse event that was generated as the
 156 // result of a touch event.
 157 EVENTS_EXPORT bool IsMouseEventFromTouch(UINT message);
 158
 159 // Converts scan code and lParam each other.  The scan code
 160 // representing an extended key contains 0xE000 bits.
 161 EVENTS_EXPORT uint16 GetScanCodeFromLParam(LPARAM lParam);
 162 EVENTS_EXPORT LPARAM GetLParamFromScanCode(uint16 scan_code);
 163
 164 #endif
 165
 166 // Registers a custom event type.
 167 EVENTS_EXPORT int RegisterCustomEventType();
 168
 169 }  // namespace ui
 170
 171 #endif  // UI_EVENTS_EVENT_UTILS_H_