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