C++ Accessible::State方法代码示例

/**
  * Gets the bounds for the areaFrame.
  *     Walks the Frame tree and checks for proper frames.
  */
void
HTMLComboboxListAccessible::GetBoundsRect(nsRect& aBounds, nsIFrame** aBoundingFrame)
{
  *aBoundingFrame = nsnull;

  Accessible* comboAcc = Parent();
  if (!comboAcc)
    return;

  if (0 == (comboAcc->State() & states::COLLAPSED)) {
    HTMLSelectListAccessible::GetBoundsRect(aBounds, aBoundingFrame);
    return;
  }

  // Get the first option.
  nsIContent* content = mContent->GetFirstChild();
  if (!content) {
    return;
  }
  nsIFrame* frame = content->GetPrimaryFrame();
  if (!frame) {
    *aBoundingFrame = nsnull;
    return;
  }

  *aBoundingFrame = frame->GetParent();
  aBounds = (*aBoundingFrame)->GetRect();
}

PRUint64
HTMLSelectOptionAccessible::NativeState()
{
  // As a HTMLSelectOptionAccessible we can have the following states:
  // SELECTABLE, SELECTED, FOCUSED, FOCUSABLE, OFFSCREEN
  // Upcall to Accessible, but skip HyperTextAccessible impl
  // because we don't want EDITABLE or SELECTABLE_TEXT
  PRUint64 state = Accessible::NativeState();

  Accessible* select = GetSelect();
  if (!select)
    return state;

  PRUint64 selectState = select->State();
  if (selectState & states::INVISIBLE)
    return state;

  // Are we selected?
  bool isSelected = false;
  nsCOMPtr<nsIDOMHTMLOptionElement> option(do_QueryInterface(mContent));
  if (option) {
    option->GetSelected(&isSelected);
    if (isSelected)
      state |= states::SELECTED;
  }

  if (selectState & states::OFFSCREEN) {
    state |= states::OFFSCREEN;
  }
  else if (selectState & states::COLLAPSED) {
    // <select> is COLLAPSED: add OFFSCREEN, if not the currently
    // visible option
    if (!isSelected) {
      state |= states::OFFSCREEN;
    }
    else {
      // Clear offscreen and invisible for currently showing option
      state &= ~(states::OFFSCREEN | states::INVISIBLE);
      state |= selectState & states::OPAQUE1;
    }
  }
  else {
    // XXX list frames are weird, don't rely on Accessible's general
    // visibility implementation unless they get reimplemented in layout
    state &= ~states::OFFSCREEN;
    // <select> is not collapsed: compare bounds to calculate OFFSCREEN
    Accessible* listAcc = Parent();
    if (listAcc) {
      PRInt32 optionX, optionY, optionWidth, optionHeight;
      PRInt32 listX, listY, listWidth, listHeight;
      GetBounds(&optionX, &optionY, &optionWidth, &optionHeight);
      listAcc->GetBounds(&listX, &listY, &listWidth, &listHeight);
      if (optionY < listY || optionY + optionHeight > listY + listHeight) {
        state |= states::OFFSCREEN;
      }
    }
  }
 
  return state;
}

nsRect
HTMLComboboxListAccessible::RelativeBounds(nsIFrame** aBoundingFrame) const
{
  *aBoundingFrame = nullptr;

  Accessible* comboAcc = Parent();
  if (!comboAcc)
    return nsRect();

  if (0 == (comboAcc->State() & states::COLLAPSED)) {
    return HTMLSelectListAccessible::RelativeBounds(aBoundingFrame);
  }

  // Get the first option.
  nsIContent* content = mContent->GetFirstChild();
  if (!content)
    return nsRect();

  nsIFrame* frame = content->GetPrimaryFrame();
  if (!frame) {
    *aBoundingFrame = nullptr;
    return nsRect();
  }

  *aBoundingFrame = frame->GetParent();
  return (*aBoundingFrame)->GetRect();
}

nsRect
HTMLSelectOptionAccessible::RelativeBounds(nsIFrame** aBoundingFrame) const
{
  Accessible* combobox = GetCombobox();
  if (combobox && (combobox->State() & states::COLLAPSED))
    return combobox->RelativeBounds(aBoundingFrame);

  return HyperTextAccessibleWrap::RelativeBounds(aBoundingFrame);
}

uint64_t
HTMLSelectOptionAccessible::NativeState() const
{
  // As a HTMLSelectOptionAccessible we can have the following states:
  // SELECTABLE, SELECTED, FOCUSED, FOCUSABLE, OFFSCREEN
  // Upcall to Accessible, but skip HyperTextAccessible impl
  // because we don't want EDITABLE or SELECTABLE_TEXT
  uint64_t state = Accessible::NativeState();

  Accessible* select = GetSelect();
  if (!select)
    return state;

  uint64_t selectState = select->State();
  if (selectState & states::INVISIBLE)
    return state;

  // Are we selected?
  HTMLOptionElement* option = HTMLOptionElement::FromNode(mContent);
  bool selected = option && option->Selected();
  if (selected)
    state |= states::SELECTED;

  if (selectState & states::OFFSCREEN) {
    state |= states::OFFSCREEN;
  } else if (selectState & states::COLLAPSED) {
    // <select> is COLLAPSED: add OFFSCREEN, if not the currently
    // visible option
    if (!selected) {
      state |= states::OFFSCREEN;
      // Ensure the invisible state is removed. Otherwise, group info will skip
      // this option. Furthermore, this gets cached and this doesn't get
      // invalidated even once the select is expanded.
      state &= ~states::INVISIBLE;
    } else {
      // Clear offscreen and invisible for currently showing option
      state &= ~(states::OFFSCREEN | states::INVISIBLE);
      state |= selectState & states::OPAQUE1;
    }
  } else {
    // XXX list frames are weird, don't rely on Accessible's general
    // visibility implementation unless they get reimplemented in layout
    state &= ~states::OFFSCREEN;
    // <select> is not collapsed: compare bounds to calculate OFFSCREEN
    Accessible* listAcc = Parent();
    if (listAcc) {
      nsIntRect optionRect = Bounds();
      nsIntRect listRect = listAcc->Bounds();
      if (optionRect.Y() < listRect.Y() ||
          optionRect.YMost() > listRect.YMost()) {
        state |= states::OFFSCREEN;
      }
    }
  }

  return state;
}

void
HTMLSelectOptionAccessible::GetBoundsRect(nsRect& aTotalBounds,
                                          nsIFrame** aBoundingFrame)
{
  Accessible* combobox = GetCombobox();
  if (combobox && (combobox->State() & states::COLLAPSED))
    combobox->GetBoundsRect(aTotalBounds, aBoundingFrame);
  else
    HyperTextAccessibleWrap::GetBoundsRect(aTotalBounds, aBoundingFrame);
}

uint64_t
HTMLSelectOptionAccessible::NativeState()
{
  // As a HTMLSelectOptionAccessible we can have the following states:
  // SELECTABLE, SELECTED, FOCUSED, FOCUSABLE, OFFSCREEN
  // Upcall to Accessible, but skip HyperTextAccessible impl
  // because we don't want EDITABLE or SELECTABLE_TEXT
  uint64_t state = Accessible::NativeState();

  Accessible* select = GetSelect();
  if (!select)
    return state;

  uint64_t selectState = select->State();
  if (selectState & states::INVISIBLE)
    return state;

  // Are we selected?
  HTMLOptionElement* option = HTMLOptionElement::FromContent(mContent);
  bool selected = option && option->Selected();
  if (selected)
    state |= states::SELECTED;

  if (selectState & states::OFFSCREEN) {
    state |= states::OFFSCREEN;
  } else if (selectState & states::COLLAPSED) {
    // <select> is COLLAPSED: add OFFSCREEN, if not the currently
    // visible option
    if (!selected) {
      state |= states::OFFSCREEN;
      state ^= states::INVISIBLE;
    } else {
      // Clear offscreen and invisible for currently showing option
      state &= ~(states::OFFSCREEN | states::INVISIBLE);
      state |= selectState & states::OPAQUE1;
    }
  } else {
    // XXX list frames are weird, don't rely on Accessible's general
    // visibility implementation unless they get reimplemented in layout
    state &= ~states::OFFSCREEN;
    // <select> is not collapsed: compare bounds to calculate OFFSCREEN
    Accessible* listAcc = Parent();
    if (listAcc) {
      nsIntRect optionRect = Bounds();
      nsIntRect listRect = listAcc->Bounds();
      if (optionRect.y < listRect.y ||
          optionRect.y + optionRect.height > listRect.y + listRect.height) {
        state |= states::OFFSCREEN;
      }
    }
  }

  return state;
}

bool
DocAccessibleChild::RecvState(const uint64_t& aID, uint64_t* aState)
{
  Accessible* acc = IdToAccessible(aID);
  if (!acc) {
    *aState = states::DEFUNCT;
    return true;
  }

  *aState = acc->State();

  return true;
}

uint64_t
XULMenuitemAccessible::NativeState() const
{
  uint64_t state = Accessible::NativeState();

  // Has Popup?
  if (mContent->NodeInfo()->Equals(nsGkAtoms::menu, kNameSpaceID_XUL)) {
    state |= states::HASPOPUP;
    if (mContent->AsElement()->HasAttr(kNameSpaceID_None, nsGkAtoms::open))
      state |= states::EXPANDED;
    else
      state |= states::COLLAPSED;
  }

  // Checkable/checked?
  static Element::AttrValuesArray strings[] =
    { nsGkAtoms::radio, nsGkAtoms::checkbox, nullptr };

  if (mContent->AsElement()->FindAttrValueIn(kNameSpaceID_None, nsGkAtoms::type,
                                             strings, eCaseMatters) >= 0) {

    // Checkable?
    state |= states::CHECKABLE;

    // Checked?
    if (mContent->AsElement()->AttrValueIs(kNameSpaceID_None, nsGkAtoms::checked,
                                           nsGkAtoms::_true, eCaseMatters))
      state |= states::CHECKED;
  }

  // Combo box listitem
  bool isComboboxOption = (Role() == roles::COMBOBOX_OPTION);
  if (isComboboxOption) {
    // Is selected?
    bool isSelected = false;
    nsCOMPtr<nsIDOMXULSelectControlItemElement>
      item(do_QueryInterface(mContent));
    NS_ENSURE_TRUE(item, state);
    item->GetSelected(&isSelected);

    // Is collapsed?
    bool isCollapsed = false;
    Accessible* parent = Parent();
    if (parent && parent->State() & states::INVISIBLE)
      isCollapsed = true;

    if (isSelected) {
      state |= states::SELECTED;

      // Selected and collapsed?
      if (isCollapsed) {
        // Set selected option offscreen/invisible according to combobox state
        Accessible* grandParent = parent->Parent();
        if (!grandParent)
          return state;
        NS_ASSERTION(grandParent->IsCombobox(),
                     "grandparent of combobox listitem is not combobox");
        uint64_t grandParentState = grandParent->State();
        state &= ~(states::OFFSCREEN | states::INVISIBLE);
        state |= (grandParentState & states::OFFSCREEN) |
                 (grandParentState & states::INVISIBLE) |
                 (grandParentState & states::OPAQUE1);
      } // isCollapsed
    } // isSelected
  } // ROLE_COMBOBOX_OPTION

  return state;
}

void
AccGroupInfo::Update()
{
  Accessible* parent = mItem->Parent();
  if (!parent)
    return;

  int32_t indexInParent = mItem->IndexInParent();
  uint32_t siblingCount = parent->ChildCount();
  if (indexInParent == -1 ||
      indexInParent >= static_cast<int32_t>(siblingCount)) {
    NS_ERROR("Wrong index in parent! Tree invalidation problem.");
    return;
  }

  int32_t level = nsAccUtils::GetARIAOrDefaultLevel(mItem);

  // Compute position in set.
  mPosInSet = 1;
  for (int32_t idx = indexInParent - 1; idx >= 0 ; idx--) {
    Accessible* sibling = parent->GetChildAt(idx);
    roles::Role siblingRole = sibling->Role();

    // If the sibling is separator then the group is ended.
    if (siblingRole == roles::SEPARATOR)
      break;

    // If sibling is not visible and hasn't the same base role.
    if (BaseRole(siblingRole) != mRole || sibling->State() & states::INVISIBLE)
      continue;

    // Check if it's hierarchical flatten structure, i.e. if the sibling
    // level is lesser than this one then group is ended, if the sibling level
    // is greater than this one then the group is split by some child elements
    // (group will be continued).
    int32_t siblingLevel = nsAccUtils::GetARIAOrDefaultLevel(sibling);
    if (siblingLevel < level) {
      mParent = sibling;
      break;
    }

    // Skip subset.
    if (siblingLevel > level)
      continue;

    // If the previous item in the group has calculated group information then
    // build group information for this item based on found one.
    if (sibling->mBits.groupInfo) {
      mPosInSet += sibling->mBits.groupInfo->mPosInSet;
      mParent = sibling->mBits.groupInfo->mParent;
      mSetSize = sibling->mBits.groupInfo->mSetSize;
      return;
    }

    mPosInSet++;
  }

  // Compute set size.
  mSetSize = mPosInSet;

  for (uint32_t idx = indexInParent + 1; idx < siblingCount; idx++) {
    Accessible* sibling = parent->GetChildAt(idx);

    roles::Role siblingRole = sibling->Role();

    // If the sibling is separator then the group is ended.
    if (siblingRole == roles::SEPARATOR)
      break;

    // If sibling is visible and has the same base role
    if (BaseRole(siblingRole) != mRole || sibling->State() & states::INVISIBLE)
      continue;

    // and check if it's hierarchical flatten structure.
    int32_t siblingLevel = nsAccUtils::GetARIAOrDefaultLevel(sibling);
    if (siblingLevel < level)
      break;

    // Skip subset.
    if (siblingLevel > level)
      continue;

    // If the next item in the group has calculated group information then
    // build group information for this item based on found one.
    if (sibling->mBits.groupInfo) {
      mParent = sibling->mBits.groupInfo->mParent;
      mSetSize = sibling->mBits.groupInfo->mSetSize;
      return;
    }

    mSetSize++;
  }

  if (mParent)
    return;

  roles::Role parentRole = parent->Role();
  if (ShouldReportRelations(mRole, parentRole))
    mParent = parent;

//.........这里部分代码省略.........

// RootAccessible protected
void
RootAccessible::ProcessDOMEvent(nsIDOMEvent* aDOMEvent)
{
  MOZ_ASSERT(aDOMEvent);
  Event* event = aDOMEvent->InternalDOMEvent();
  nsCOMPtr<nsINode> origTargetNode = do_QueryInterface(event->GetOriginalTarget());

  nsAutoString eventType;
  aDOMEvent->GetType(eventType);

#ifdef A11Y_LOG
  if (logging::IsEnabled(logging::eDOMEvents))
    logging::DOMEvent("processed", origTargetNode, eventType);
#endif

  if (eventType.EqualsLiteral("popuphiding")) {
    HandlePopupHidingEvent(origTargetNode);
    return;
  }

  DocAccessible* targetDocument = GetAccService()->
    GetDocAccessible(origTargetNode->OwnerDoc());
  NS_ASSERTION(targetDocument, "No document while accessible is in document?!");

  Accessible* accessible = 
    targetDocument->GetAccessibleOrContainer(origTargetNode);
  if (!accessible)
    return;

#ifdef MOZ_XUL
  XULTreeAccessible* treeAcc = accessible->AsXULTree();
  if (treeAcc) {
    if (eventType.EqualsLiteral("TreeRowCountChanged")) {
      HandleTreeRowCountChangedEvent(aDOMEvent, treeAcc);
      return;
    }

    if (eventType.EqualsLiteral("TreeInvalidated")) {
      HandleTreeInvalidatedEvent(aDOMEvent, treeAcc);
      return;
    }
  }
#endif

  if (eventType.EqualsLiteral("RadioStateChange")) {
    uint64_t state = accessible->State();
    bool isEnabled = (state & (states::CHECKED | states::SELECTED)) != 0;

    if (accessible->NeedsDOMUIEvent()) {
      nsRefPtr<AccEvent> accEvent =
        new AccStateChangeEvent(accessible, states::CHECKED, isEnabled);
      nsEventShell::FireEvent(accEvent);
    }

    if (isEnabled) {
      FocusMgr()->ActiveItemChanged(accessible);
#ifdef A11Y_LOG
      if (logging::IsEnabled(logging::eFocus))
        logging::ActiveItemChangeCausedBy("RadioStateChange", accessible);
#endif
    }

    return;
  }

  if (eventType.EqualsLiteral("CheckboxStateChange")) {
    if (accessible->NeedsDOMUIEvent()) {
      uint64_t state = accessible->State();
      bool isEnabled = !!(state & states::CHECKED);

      nsRefPtr<AccEvent> accEvent =
        new AccStateChangeEvent(accessible, states::CHECKED, isEnabled);
      nsEventShell::FireEvent(accEvent);
    }
    return;
  }

  Accessible* treeItemAcc = nullptr;
#ifdef MOZ_XUL
  // If it's a tree element, need the currently selected item.
  if (treeAcc) {
    treeItemAcc = accessible->CurrentItem();
    if (treeItemAcc)
      accessible = treeItemAcc;
  }

  if (treeItemAcc && eventType.EqualsLiteral("OpenStateChange")) {
    uint64_t state = accessible->State();
    bool isEnabled = (state & states::EXPANDED) != 0;

    nsRefPtr<AccEvent> accEvent =
      new AccStateChangeEvent(accessible, states::EXPANDED, isEnabled);
    nsEventShell::FireEvent(accEvent);
    return;
  }

  nsINode* targetNode = accessible->GetNode();
  if (treeItemAcc && eventType.EqualsLiteral("select")) {
    // XXX: We shouldn't be based on DOM select event which doesn't provide us
//.........这里部分代码省略.........

// RootAccessible protected
void
RootAccessible::ProcessDOMEvent(nsIDOMEvent* aDOMEvent)
{
  nsCOMPtr<nsIDOMNSEvent> DOMNSEvent(do_QueryInterface(aDOMEvent));
  nsCOMPtr<nsIDOMEventTarget> DOMEventTarget;
  DOMNSEvent->GetOriginalTarget(getter_AddRefs(DOMEventTarget));
  nsCOMPtr<nsINode> origTargetNode(do_QueryInterface(DOMEventTarget));

  nsAutoString eventType;
  aDOMEvent->GetType(eventType);

  if (eventType.EqualsLiteral("popuphiding")) {
    HandlePopupHidingEvent(origTargetNode);
    return;
  }

  DocAccessible* targetDocument = GetAccService()->
    GetDocAccessible(origTargetNode->OwnerDoc());
  NS_ASSERTION(targetDocument, "No document while accessible is in document?!");

  Accessible* accessible = 
    targetDocument->GetAccessibleOrContainer(origTargetNode);
  if (!accessible)
    return;

  nsINode* targetNode = accessible->GetNode();

#ifdef MOZ_XUL
  XULTreeAccessible* treeAcc = accessible->AsXULTree();
  if (treeAcc) {
    if (eventType.EqualsLiteral("TreeRowCountChanged")) {
      HandleTreeRowCountChangedEvent(aDOMEvent, treeAcc);
      return;
    }

    if (eventType.EqualsLiteral("TreeInvalidated")) {
      HandleTreeInvalidatedEvent(aDOMEvent, treeAcc);
      return;
    }
  }
#endif

  if (eventType.EqualsLiteral("RadioStateChange")) {
    PRUint64 state = accessible->State();

    // radiogroup in prefWindow is exposed as a list,
    // and panebutton is exposed as XULListitem in A11y.
    // XULListitemAccessible::GetStateInternal uses STATE_SELECTED in this case,
    // so we need to check states::SELECTED also.
    bool isEnabled = (state & (states::CHECKED | states::SELECTED)) != 0;

    nsRefPtr<AccEvent> accEvent =
      new AccStateChangeEvent(accessible, states::CHECKED, isEnabled);
    nsEventShell::FireEvent(accEvent);

    if (isEnabled) {
      FocusMgr()->ActiveItemChanged(accessible);
      A11YDEBUG_FOCUS_ACTIVEITEMCHANGE_CAUSE("RadioStateChange", accessible)
    }

    return;
  }

void DocAccessibleWrap::CacheViewportCallback(nsITimer* aTimer,
                                              void* aDocAccParam) {
  RefPtr<DocAccessibleWrap> docAcc(
      dont_AddRef(reinterpret_cast<DocAccessibleWrap*>(aDocAccParam)));
  if (!docAcc) {
    return;
  }

  nsIPresShell* presShell = docAcc->PresShell();
  if (!presShell) {
    return;
  }
  nsIFrame* rootFrame = presShell->GetRootFrame();
  if (!rootFrame) {
    return;
  }

  nsTArray<nsIFrame*> frames;
  nsIScrollableFrame* sf = presShell->GetRootScrollFrameAsScrollable();
  nsRect scrollPort = sf ? sf->GetScrollPortRect() : rootFrame->GetRect();

  nsLayoutUtils::GetFramesForArea(
      presShell->GetRootFrame(), scrollPort, frames,
      nsLayoutUtils::FrameForPointFlags::ONLY_VISIBLE);
  AccessibleHashtable inViewAccs;
  for (size_t i = 0; i < frames.Length(); i++) {
    nsIContent* content = frames.ElementAt(i)->GetContent();
    if (!content) {
      continue;
    }

    Accessible* visibleAcc = docAcc->GetAccessibleOrContainer(content);
    if (!visibleAcc) {
      continue;
    }

    for (Accessible* acc = visibleAcc; acc && acc != docAcc->Parent();
         acc = acc->Parent()) {
      if (inViewAccs.Contains(acc->UniqueID())) {
        break;
      }
      inViewAccs.Put(acc->UniqueID(), acc);
    }
  }

  if (IPCAccessibilityActive()) {
    DocAccessibleChild* ipcDoc = docAcc->IPCDoc();
    nsTArray<BatchData> cacheData(inViewAccs.Count());
    for (auto iter = inViewAccs.Iter(); !iter.Done(); iter.Next()) {
      Accessible* accessible = iter.Data();
      auto uid = accessible->IsDoc() && accessible->AsDoc()->IPCDoc()
                     ? 0
                     : reinterpret_cast<uint64_t>(accessible->UniqueID());
      cacheData.AppendElement(
          BatchData(accessible->Document()->IPCDoc(), uid, accessible->State(),
                    accessible->Bounds(), accessible->ActionCount(), nsString(),
                    nsString(), nsString(), UnspecifiedNaN<double>(),
                    UnspecifiedNaN<double>(), UnspecifiedNaN<double>(),
                    UnspecifiedNaN<double>(), nsTArray<Attribute>()));
    }

    ipcDoc->SendBatch(eBatch_Viewport, cacheData);
  } else if (SessionAccessibility* sessionAcc =
                 SessionAccessibility::GetInstanceFor(docAcc)) {
    nsTArray<AccessibleWrap*> accessibles(inViewAccs.Count());
    for (auto iter = inViewAccs.Iter(); !iter.Done(); iter.Next()) {
      accessibles.AppendElement(
          static_cast<AccessibleWrap*>(iter.Data().get()));
    }

    sessionAcc->ReplaceViewportCache(accessibles);
  }

  if (docAcc->mCacheRefreshTimer) {
    docAcc->mCacheRefreshTimer = nullptr;
  }
}