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