accessible/generic/BaseAccessibles.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "BaseAccessibles.h"
   7
   8 #include "Accessible-inl.h"
   9 #include "HyperTextAccessibleWrap.h"
  10 #include "nsAccessibilityService.h"
  11 #include "nsAccUtils.h"
  12 #include "nsCoreUtils.h"
  13 #include "Role.h"
  14 #include "States.h"
  15 #include "nsIURI.h"
  16
  17 using namespace mozilla::a11y;
  18
  19 ////////////////////////////////////////////////////////////////////////////////
  20 // LeafAccessible
  21 ////////////////////////////////////////////////////////////////////////////////
  22
  23 LeafAccessible::
  24   LeafAccessible(nsIContent* aContent, DocAccessible* aDoc) :
  25   AccessibleWrap(aContent, aDoc)
  26 {
  27 }
  28
  29 NS_IMPL_ISUPPORTS_INHERITED0(LeafAccessible, Accessible)
  30
  31 ////////////////////////////////////////////////////////////////////////////////
  32 // LeafAccessible: Accessible public
  33
  34 Accessible*
  35 LeafAccessible::ChildAtPoint(int32_t aX, int32_t aY,
  36                              EWhichChildAtPoint aWhichChild)
  37 {
  38   // Don't walk into leaf accessibles.
  39   return this;
  40 }
  41
  42 bool
  43 LeafAccessible::InsertChildAt(uint32_t aIndex, Accessible* aChild)
  44 {
  45   NS_NOTREACHED("InsertChildAt called on leaf accessible!");
  46   return false;
  47 }
  48
  49 bool
  50 LeafAccessible::RemoveChild(Accessible* aChild)
  51 {
  52   NS_NOTREACHED("RemoveChild called on leaf accessible!");
  53   return false;
  54 }
  55
  56 ////////////////////////////////////////////////////////////////////////////////
  57 // LeafAccessible: Accessible private
  58
  59 void
  60 LeafAccessible::CacheChildren()
  61 {
  62   // No children for leaf accessible.
  63 }
  64
  65
  66 ////////////////////////////////////////////////////////////////////////////////
  67 // LinkableAccessible
  68 ////////////////////////////////////////////////////////////////////////////////
  69
  70 LinkableAccessible::
  71   LinkableAccessible(nsIContent* aContent, DocAccessible* aDoc) :
  72   AccessibleWrap(aContent, aDoc),
  73   mActionAcc(nullptr),
  74   mIsLink(false),
  75   mIsOnclick(false)
  76 {
  77 }
  78
  79 NS_IMPL_ISUPPORTS_INHERITED0(LinkableAccessible, AccessibleWrap)
  80
  81 ////////////////////////////////////////////////////////////////////////////////
  82 // LinkableAccessible. nsIAccessible
  83
  84 NS_IMETHODIMP
  85 LinkableAccessible::TakeFocus()
  86 {
  87   return mActionAcc ? mActionAcc->TakeFocus() : AccessibleWrap::TakeFocus();
  88 }
  89
  90 uint64_t
  91 LinkableAccessible::NativeLinkState() const
  92 {
  93   if (mIsLink)
  94     return states::LINKED | (mActionAcc->LinkState() & states::TRAVERSED);
  95
  96   return 0;
  97 }
  98
  99 void
 100 LinkableAccessible::Value(nsString& aValue)
 101 {
 102   aValue.Truncate();
 103
 104   Accessible::Value(aValue);
 105   if (!aValue.IsEmpty())
 106     return;
 107
 108   if (aValue.IsEmpty() && mIsLink)
 109     mActionAcc->Value(aValue);
 110 }
 111
 112
 113 uint8_t
 114 LinkableAccessible::ActionCount()
 115 {
 116   return (mIsOnclick || mIsLink) ? 1 : 0;
 117 }
 118
 119 NS_IMETHODIMP
 120 LinkableAccessible::GetActionName(uint8_t aIndex, nsAString& aName)
 121 {
 122   aName.Truncate();
 123
 124   // Action 0 (default action): Jump to link
 125   if (aIndex == eAction_Jump) {
 126     if (mIsLink) {
 127       aName.AssignLiteral("jump");
 128       return NS_OK;
 129     }
 130     else if (mIsOnclick) {
 131       aName.AssignLiteral("click");
 132       return NS_OK;
 133     }
 134     return NS_ERROR_NOT_IMPLEMENTED;
 135   }
 136   return NS_ERROR_INVALID_ARG;
 137 }
 138
 139 NS_IMETHODIMP
 140 LinkableAccessible::DoAction(uint8_t aIndex)
 141 {
 142   if (aIndex != eAction_Jump)
 143     return NS_ERROR_INVALID_ARG;
 144
 145   return mActionAcc ? mActionAcc->DoAction(aIndex) :
 146     AccessibleWrap::DoAction(aIndex);
 147 }
 148
 149 KeyBinding
 150 LinkableAccessible::AccessKey() const
 151 {
 152   return mActionAcc ?
 153     mActionAcc->AccessKey() : Accessible::AccessKey();
 154 }
 155
 156 ////////////////////////////////////////////////////////////////////////////////
 157 // LinkableAccessible. Accessible
 158
 159 void
 160 LinkableAccessible::Shutdown()
 161 {
 162   mIsLink = false;
 163   mIsOnclick = false;
 164   mActionAcc = nullptr;
 165   AccessibleWrap::Shutdown();
 166 }
 167
 168 ////////////////////////////////////////////////////////////////////////////////
 169 // LinkableAccessible: HyperLinkAccessible
 170
 171 already_AddRefed<nsIURI>
 172 LinkableAccessible::AnchorURIAt(uint32_t aAnchorIndex)
 173 {
 174   if (mIsLink) {
 175     NS_ASSERTION(mActionAcc->IsLink(),
 176                  "nsIAccessibleHyperLink isn't implemented.");
 177
 178     if (mActionAcc->IsLink())
 179       return mActionAcc->AnchorURIAt(aAnchorIndex);
 180   }
 181
 182   return nullptr;
 183 }
 184
 185 ////////////////////////////////////////////////////////////////////////////////
 186 // LinkableAccessible: Accessible protected
 187
 188 void
 189 LinkableAccessible::BindToParent(Accessible* aParent,
 190                                  uint32_t aIndexInParent)
 191 {
 192   AccessibleWrap::BindToParent(aParent, aIndexInParent);
 193
 194   // Cache action content.
 195   mActionAcc = nullptr;
 196   mIsLink = false;
 197   mIsOnclick = false;
 198
 199   if (nsCoreUtils::HasClickListener(mContent)) {
 200     mIsOnclick = true;
 201     return;
 202   }
 203
 204   // XXX: The logic looks broken since the click listener may be registered
 205   // on non accessible node in parent chain but this node is skipped when tree
 206   // is traversed.
 207   Accessible* walkUpAcc = this;
 208   while ((walkUpAcc = walkUpAcc->Parent()) && !walkUpAcc->IsDoc()) {
 209     if (walkUpAcc->LinkState() & states::LINKED) {
 210       mIsLink = true;
 211       mActionAcc = walkUpAcc;
 212       return;
 213     }
 214
 215     if (nsCoreUtils::HasClickListener(walkUpAcc->GetContent())) {
 216       mActionAcc = walkUpAcc;
 217       mIsOnclick = true;
 218       return;
 219     }
 220   }
 221 }
 222
 223 void
 224 LinkableAccessible::UnbindFromParent()
 225 {
 226   mActionAcc = nullptr;
 227   mIsLink = false;
 228   mIsOnclick = false;
 229
 230   AccessibleWrap::UnbindFromParent();
 231 }
 232
 233 ////////////////////////////////////////////////////////////////////////////////
 234 // EnumRoleAccessible
 235 ////////////////////////////////////////////////////////////////////////////////
 236
 237 EnumRoleAccessible::
 238   EnumRoleAccessible(nsIContent* aNode, DocAccessible* aDoc, roles::Role aRole) :
 239   AccessibleWrap(aNode, aDoc), mRole(aRole)
 240 {
 241 }
 242
 243 NS_IMPL_ISUPPORTS_INHERITED0(EnumRoleAccessible, Accessible)
 244
 245 role
 246 EnumRoleAccessible::NativeRole()
 247 {
 248   return mRole;
 249 }
 250
 251 ////////////////////////////////////////////////////////////////////////////////
 252 // DummyAccessible
 253 ////////////////////////////////////////////////////////////////////////////////
 254
 255 uint64_t
 256 DummyAccessible::NativeState()
 257 {
 258   return 0;
 259 }
 260 uint64_t
 261 DummyAccessible::NativeInteractiveState() const
 262 {
 263   return 0;
 264 }
 265
 266 uint64_t
 267 DummyAccessible::NativeLinkState() const
 268 {
 269   return 0;
 270 }
 271
 272 bool
 273 DummyAccessible::NativelyUnavailable() const
 274 {
 275   return false;
 276 }
 277
 278 void
 279 DummyAccessible::ApplyARIAState(uint64_t* aState) const
 280 {
 281 }