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/basictypes.h"
   9 #include "base/event_types.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "base/strings/string16.h"
  12 #include "ui/events/event_constants.h"
  13 #include "ui/events/keycodes/keyboard_codes.h"
  14 #include "ui/gfx/display.h"
  15 #include "ui/gfx/native_widget_types.h"
  16 #include "ui/events/events_export.h"
  17
  18 #if defined(OS_WIN)
  19 #include <windows.h>
  20 #endif
  21
  22 namespace gfx {
  23 class Point;
  24 class Vector2d;
  25 }
  26
  27 namespace base {
  28 class TimeDelta;
  29 }
  30
  31 namespace ui {
  32
  33 class Event;
  34 class MouseEvent;
  35
  36 // Updates the list of devices for cached properties.
  37 EVENTS_EXPORT void UpdateDeviceList();
  38
  39 // Returns a ui::Event wrapping a native event. Ownership of the returned value
  40 // is transferred to the caller.
  41 EVENTS_EXPORT scoped_ptr<Event> EventFromNative(
  42     const base::NativeEvent& native_event);
  43
  44 // Get the EventType from a native event.
  45 EVENTS_EXPORT EventType EventTypeFromNative(
  46     const base::NativeEvent& native_event);
  47
  48 // Get the EventFlags from a native event.
  49 EVENTS_EXPORT int EventFlagsFromNative(const base::NativeEvent& native_event);
  50
  51 // Get the timestamp from a native event.
  52 EVENTS_EXPORT base::TimeDelta EventTimeFromNative(
  53     const base::NativeEvent& native_event);
  54
  55 // Create a timestamp based on the current time.
  56 EVENTS_EXPORT base::TimeDelta EventTimeForNow();
  57
  58 // Get the location from a native event.  The coordinate system of the resultant
  59 // |Point| has the origin at top-left of the "root window".  The nature of
  60 // this "root window" and how it maps to platform-specific drawing surfaces is
  61 // defined in ui/aura/root_window.* and ui/aura/window_tree_host*.
  62 // TODO(tdresser): Return gfx::PointF here. See crbug.com/337827.
  63 EVENTS_EXPORT gfx::Point EventLocationFromNative(
  64     const base::NativeEvent& native_event);
  65
  66 // Gets the location in native system coordinate space.
  67 EVENTS_EXPORT gfx::Point EventSystemLocationFromNative(
  68     const base::NativeEvent& native_event);
  69
  70 #if defined(USE_X11)
  71 // Returns the 'real' button for an event. The button reported in slave events
  72 // does not take into account any remapping (e.g. using xmodmap), while the
  73 // button reported in master events do. This is a utility function to always
  74 // return the mapped button.
  75 EVENTS_EXPORT int EventButtonFromNative(const base::NativeEvent& native_event);
  76 #endif
  77
  78 // Returns the KeyboardCode from a native event.
  79 EVENTS_EXPORT KeyboardCode KeyboardCodeFromNative(
  80     const base::NativeEvent& native_event);
  81
  82 // Returns the DOM KeyboardEvent code (physical location in the
  83 // keyboard) from a native event.  The ownership of the return value
  84 // is NOT trasferred to the caller.
  85 EVENTS_EXPORT const char* CodeFromNative(
  86     const base::NativeEvent& native_event);
  87
  88 // Returns the platform related key code. For X11, it is xksym value.
  89 EVENTS_EXPORT uint32 PlatformKeycodeFromNative(
  90     const base::NativeEvent& native_event);
  91
  92 // Returns a control character sequences from a |windows_key_code|.
  93 EVENTS_EXPORT base::char16 GetControlCharacterForKeycode(int windows_key_code,
  94                                                          bool shift);
  95
  96 // Returns true if the keyboard event is a character event rather than
  97 // a keystroke event.
  98 EVENTS_EXPORT bool IsCharFromNative(const base::NativeEvent& native_event);
  99
 100 // Returns the flags of the button that changed during a press/release.
 101 EVENTS_EXPORT int GetChangedMouseButtonFlagsFromNative(
 102     const base::NativeEvent& native_event);
 103
 104 // Gets the mouse wheel offsets from a native event.
 105 EVENTS_EXPORT gfx::Vector2d GetMouseWheelOffset(
 106     const base::NativeEvent& native_event);
 107
 108 // Returns a copy of |native_event|. Depending on the platform, this copy may
 109 // need to be deleted with ReleaseCopiedNativeEvent().
 110 base::NativeEvent CopyNativeEvent(
 111     const base::NativeEvent& native_event);
 112
 113 // Delete a |native_event| previously created by CopyNativeEvent().
 114 void ReleaseCopiedNativeEvent(
 115     const base::NativeEvent& native_event);
 116
 117 // Gets the touch id from a native event.
 118 EVENTS_EXPORT int GetTouchId(const base::NativeEvent& native_event);
 119
 120 // Increases the number of times |ClearTouchIdIfReleased| needs to be called on
 121 // an event with a given touch id before it will actually be cleared.
 122 EVENTS_EXPORT void IncrementTouchIdRefCount(
 123     const base::NativeEvent& native_event);
 124
 125 // Clear the touch id from bookkeeping if it is a release/cancel event.
 126 EVENTS_EXPORT void ClearTouchIdIfReleased(
 127     const base::NativeEvent& native_event);
 128
 129 // Gets the radius along the X/Y axis from a native event. Default is 1.0.
 130 EVENTS_EXPORT float GetTouchRadiusX(const base::NativeEvent& native_event);
 131 EVENTS_EXPORT float GetTouchRadiusY(const base::NativeEvent& native_event);
 132
 133 // Gets the angle of the major axis away from the X axis. Default is 0.0.
 134 EVENTS_EXPORT float GetTouchAngle(const base::NativeEvent& native_event);
 135
 136 // Gets the force from a native_event. Normalized to be [0, 1]. Default is 0.0.
 137 EVENTS_EXPORT float GetTouchForce(const base::NativeEvent& native_event);
 138
 139 // Gets the fling velocity from a native event. is_cancel is set to true if
 140 // this was a tap down, intended to stop an ongoing fling.
 141 EVENTS_EXPORT bool GetFlingData(const base::NativeEvent& native_event,
 142                                 float* vx,
 143                                 float* vy,
 144                                 float* vx_ordinal,
 145                                 float* vy_ordinal,
 146                                 bool* is_cancel);
 147
 148 // Returns whether this is a scroll event and optionally gets the amount to be
 149 // scrolled. |x_offset|, |y_offset| and |finger_count| can be NULL.
 150 EVENTS_EXPORT bool GetScrollOffsets(const base::NativeEvent& native_event,
 151                                     float* x_offset,
 152                                     float* y_offset,
 153                                     float* x_offset_ordinal,
 154                                     float* y_offset_ordinal,
 155                                     int* finger_count);
 156
 157 // Returns whether natural scrolling should be used for touchpad.
 158 EVENTS_EXPORT bool ShouldDefaultToNaturalScroll();
 159
 160 // Returns whether or not the internal display produces touch events.
 161 EVENTS_EXPORT gfx::Display::TouchSupport GetInternalDisplayTouchSupport();
 162
 163 #if defined(OS_WIN)
 164 EVENTS_EXPORT int GetModifiersFromACCEL(const ACCEL& accel);
 165 EVENTS_EXPORT int GetModifiersFromKeyState();
 166
 167 // Returns true if |message| identifies a mouse event that was generated as the
 168 // result of a touch event.
 169 EVENTS_EXPORT bool IsMouseEventFromTouch(UINT message);
 170
 171 // Converts scan code and lParam each other.  The scan code
 172 // representing an extended key contains 0xE000 bits.
 173 EVENTS_EXPORT uint16 GetScanCodeFromLParam(LPARAM lParam);
 174 EVENTS_EXPORT LPARAM GetLParamFromScanCode(uint16 scan_code);
 175
 176 #endif
 177
 178 #if defined(USE_X11)
 179 // Update the native X11 event to correspond to the new flags.
 180 EVENTS_EXPORT void UpdateX11EventForFlags(Event* event);
 181 // Update the native X11 event to correspond to the new button flags.
 182 EVENTS_EXPORT void UpdateX11EventForChangedButtonFlags(MouseEvent* event);
 183 #endif
 184
 185 // Registers a custom event type.
 186 EVENTS_EXPORT int RegisterCustomEventType();
 187
 188 }  // namespace ui
 189
 190 #endif  // UI_EVENTS_EVENT_UTILS_H_