dom/events/WheelEvent.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   5  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/dom/WheelEvent.h"
   8 #include "mozilla/MouseEvents.h"
   9 #include "prtime.h"
  10
  11 namespace mozilla {
  12 namespace dom {
  13
  14 WheelEvent::WheelEvent(EventTarget* aOwner,
  15                        nsPresContext* aPresContext,
  16                        WidgetWheelEvent* aWheelEvent)
  17   : MouseEvent(aOwner, aPresContext,
  18                aWheelEvent ? aWheelEvent :
  19                              new WidgetWheelEvent(false, 0, nullptr))
  20   , mAppUnitsPerDevPixel(0)
  21 {
  22   if (aWheelEvent) {
  23     mEventIsInternal = false;
  24     // If the delta mode is pixel, the WidgetWheelEvent's delta values are in
  25     // device pixels.  However, JS contents need the delta values in CSS pixels.
  26     // We should store the value of mAppUnitsPerDevPixel here because
  27     // it might be changed by changing zoom or something.
  28     if (aWheelEvent->deltaMode == nsIDOMWheelEvent::DOM_DELTA_PIXEL) {
  29       mAppUnitsPerDevPixel = aPresContext->AppUnitsPerDevPixel();
  30     }
  31   } else {
  32     mEventIsInternal = true;
  33     mEvent->time = PR_Now();
  34     mEvent->refPoint.x = mEvent->refPoint.y = 0;
  35     mEvent->AsWheelEvent()->inputSource = nsIDOMMouseEvent::MOZ_SOURCE_UNKNOWN;
  36   }
  37 }
  38
  39 NS_IMPL_ADDREF_INHERITED(WheelEvent, MouseEvent)
  40 NS_IMPL_RELEASE_INHERITED(WheelEvent, MouseEvent)
  41
  42 NS_INTERFACE_MAP_BEGIN(WheelEvent)
  43   NS_INTERFACE_MAP_ENTRY(nsIDOMWheelEvent)
  44 NS_INTERFACE_MAP_END_INHERITING(MouseEvent)
  45
  46 NS_IMETHODIMP
  47 WheelEvent::InitWheelEvent(const nsAString& aType,
  48                            bool aCanBubble,
  49                            bool aCancelable,
  50                            nsIDOMWindow* aView,
  51                            int32_t aDetail,
  52                            int32_t aScreenX,
  53                            int32_t aScreenY,
  54                            int32_t aClientX,
  55                            int32_t aClientY,
  56                            uint16_t aButton,
  57                            nsIDOMEventTarget* aRelatedTarget,
  58                            const nsAString& aModifiersList,
  59                            double aDeltaX,
  60                            double aDeltaY,
  61                            double aDeltaZ,
  62                            uint32_t aDeltaMode)
  63 {
  64   nsresult rv =
  65     MouseEvent::InitMouseEvent(aType, aCanBubble, aCancelable, aView, aDetail,
  66                                aScreenX, aScreenY, aClientX, aClientY, aButton,
  67                                aRelatedTarget, aModifiersList);
  68   NS_ENSURE_SUCCESS(rv, rv);
  69
  70   WidgetWheelEvent* wheelEvent = mEvent->AsWheelEvent();
  71   wheelEvent->deltaX = aDeltaX;
  72   wheelEvent->deltaY = aDeltaY;
  73   wheelEvent->deltaZ = aDeltaZ;
  74   wheelEvent->deltaMode = aDeltaMode;
  75
  76   return NS_OK;
  77 }
  78
  79 double
  80 WheelEvent::DeltaX()
  81 {
  82   if (!mAppUnitsPerDevPixel) {
  83     return mEvent->AsWheelEvent()->deltaX;
  84   }
  85   return mEvent->AsWheelEvent()->deltaX *
  86     mAppUnitsPerDevPixel / nsPresContext::AppUnitsPerCSSPixel();
  87 }
  88
  89 NS_IMETHODIMP
  90 WheelEvent::GetDeltaX(double* aDeltaX)
  91 {
  92   NS_ENSURE_ARG_POINTER(aDeltaX);
  93
  94   *aDeltaX = DeltaX();
  95   return NS_OK;
  96 }
  97
  98 double
  99 WheelEvent::DeltaY()
 100 {
 101   if (!mAppUnitsPerDevPixel) {
 102     return mEvent->AsWheelEvent()->deltaY;
 103   }
 104   return mEvent->AsWheelEvent()->deltaY *
 105     mAppUnitsPerDevPixel / nsPresContext::AppUnitsPerCSSPixel();
 106 }
 107
 108 NS_IMETHODIMP
 109 WheelEvent::GetDeltaY(double* aDeltaY)
 110 {
 111   NS_ENSURE_ARG_POINTER(aDeltaY);
 112
 113   *aDeltaY = DeltaY();
 114   return NS_OK;
 115 }
 116
 117 double
 118 WheelEvent::DeltaZ()
 119 {
 120   if (!mAppUnitsPerDevPixel) {
 121     return mEvent->AsWheelEvent()->deltaZ;
 122   }
 123   return mEvent->AsWheelEvent()->deltaZ *
 124     mAppUnitsPerDevPixel / nsPresContext::AppUnitsPerCSSPixel();
 125 }
 126
 127 NS_IMETHODIMP
 128 WheelEvent::GetDeltaZ(double* aDeltaZ)
 129 {
 130   NS_ENSURE_ARG_POINTER(aDeltaZ);
 131
 132   *aDeltaZ = DeltaZ();
 133   return NS_OK;
 134 }
 135
 136 uint32_t
 137 WheelEvent::DeltaMode()
 138 {
 139   return mEvent->AsWheelEvent()->deltaMode;
 140 }
 141
 142 NS_IMETHODIMP
 143 WheelEvent::GetDeltaMode(uint32_t* aDeltaMode)
 144 {
 145   NS_ENSURE_ARG_POINTER(aDeltaMode);
 146
 147   *aDeltaMode = DeltaMode();
 148   return NS_OK;
 149 }
 150
 151 static void
 152 GetModifierList(bool aCtrl, bool aShift, bool aAlt, bool aMeta,
 153                 nsAString& aModifierList)
 154 {
 155   if (aCtrl) {
 156     aModifierList.AppendLiteral(NS_DOM_KEYNAME_CONTROL);
 157   }
 158   if (aShift) {
 159     if (!aModifierList.IsEmpty()) {
 160       aModifierList.Append(' ');
 161     }
 162     aModifierList.AppendLiteral(NS_DOM_KEYNAME_SHIFT);
 163   }
 164   if (aAlt) {
 165     if (!aModifierList.IsEmpty()) {
 166       aModifierList.Append(' ');
 167     }
 168     aModifierList.AppendLiteral(NS_DOM_KEYNAME_ALT);
 169   }
 170   if (aMeta) {
 171     if (!aModifierList.IsEmpty()) {
 172       aModifierList.Append(' ');
 173     }
 174     aModifierList.AppendLiteral(NS_DOM_KEYNAME_META);
 175   }
 176 }
 177
 178 already_AddRefed<WheelEvent>
 179 WheelEvent::Constructor(const GlobalObject& aGlobal,
 180                         const nsAString& aType,
 181                         const WheelEventInit& aParam,
 182                         ErrorResult& aRv)
 183 {
 184   nsCOMPtr<EventTarget> t = do_QueryInterface(aGlobal.GetAsSupports());
 185   nsRefPtr<WheelEvent> e = new WheelEvent(t, nullptr, nullptr);
 186   bool trusted = e->Init(t);
 187   nsAutoString modifierList;
 188   GetModifierList(aParam.mCtrlKey, aParam.mShiftKey,
 189                   aParam.mAltKey, aParam.mMetaKey,
 190                   modifierList);
 191   aRv = e->InitWheelEvent(aType, aParam.mBubbles, aParam.mCancelable,
 192                           aParam.mView, aParam.mDetail,
 193                           aParam.mScreenX, aParam.mScreenY,
 194                           aParam.mClientX, aParam.mClientY,
 195                           aParam.mButton, aParam.mRelatedTarget,
 196                           modifierList, aParam.mDeltaX,
 197                           aParam.mDeltaY, aParam.mDeltaZ, aParam.mDeltaMode);
 198   e->mEvent->AsWheelEvent()->buttons = aParam.mButtons;
 199   e->SetTrusted(trusted);
 200   return e.forget();
 201 }
 202
 203 } // namespace dom
 204 } // namespace mozilla
 205
 206 using namespace mozilla;
 207 using namespace mozilla::dom;
 208
 209 nsresult
 210 NS_NewDOMWheelEvent(nsIDOMEvent** aInstancePtrResult,
 211                     EventTarget* aOwner,
 212                     nsPresContext* aPresContext,
 213                     WidgetWheelEvent* aEvent)
 214 {
 215   WheelEvent* it = new WheelEvent(aOwner, aPresContext, aEvent);
 216   NS_ADDREF(it);
 217   *aInstancePtrResult = static_cast<Event*>(it);
 218   return NS_OK;
 219 }