Accessible*
TreeWalker::AccessibleFor(nsIContent* aNode, uint32_t aFlags, bool* aSkipSubtree)
{
// Ignore the accessible and its subtree if it was repositioned by means
// of aria-owns.
Accessible* child = mDoc->GetAccessible(aNode);
if (child) {
if (child->IsRelocated()) {
*aSkipSubtree = true;
return nullptr;
}
return child;
}
// Create an accessible if allowed.
if (!(aFlags & eWalkCache) && mContext->IsAcceptableChild(aNode)) {
// We may have ARIA owned element in the dependent attributes map, but the
// element may be not allowed for this ARIA owns relation, if the relation
// crosses out XBL anonymous content boundaries. In this case we won't
// create an accessible object for it, when aria-owns is processed, which
// may make the element subtree inaccessible. To avoid that let's create
// an accessible object now, and later, if allowed, move it in the tree,
// when aria-owns relation is processed.
if (mDoc->RelocateARIAOwnedIfNeeded(aNode) && !aNode->IsXULElement()) {
*aSkipSubtree = true;
return nullptr;
}
return GetAccService()->CreateAccessible(aNode, mContext, aSkipSubtree);
}
return nullptr;
}
bool
TreeWalker::Seek(nsIContent* aChildNode)
{
MOZ_ASSERT(aChildNode, "Child cannot be null");
Reset();
if (mAnchorNode == aChildNode) {
return true;
}
nsIContent* childNode = nullptr;
nsINode* parentNode = aChildNode;
do {
childNode = parentNode->AsContent();
parentNode = childNode->HasFlag(NODE_MAY_BE_IN_BINDING_MNGR) &&
(mChildFilter & nsIContent::eAllButXBL) ?
childNode->GetParentNode() : childNode->GetFlattenedTreeParent();
if (!parentNode || !parentNode->IsElement()) {
return false;
}
// If ARIA owned child.
Accessible* child = mDoc->GetAccessible(childNode);
if (child && child->IsRelocated()) {
MOZ_ASSERT(!(mFlags & eScoped),
"Walker should not be scoped when seeking into relocated children");
if (child->Parent() != mContext) {
return false;
}
Accessible* ownedChild = nullptr;
while ((ownedChild = mDoc->ARIAOwnedAt(mContext, mARIAOwnsIdx++)) &&
ownedChild != child);
MOZ_ASSERT(ownedChild, "A child has to be in ARIA owned elements");
mPhase = eAtARIAOwns;
return true;
}
// Look in DOM.
dom::AllChildrenIterator* iter = PrependState(parentNode->AsElement(), true);
if (!iter->Seek(childNode)) {
return false;
}
if (parentNode == mAnchorNode) {
mPhase = eAtDOM;
return true;
}
} while (true);
return false;
}
Accessible*
TreeWalker::AccessibleFor(nsIContent* aNode, uint32_t aFlags, bool* aSkipSubtree)
{
Accessible* child = nullptr;
if (aFlags & eWalkCache) {
child = mDoc->GetAccessible(aNode);
}
else if (mContext->IsAcceptableChild(aNode)) {
child = GetAccService()->
GetOrCreateAccessible(aNode, mContext, aSkipSubtree);
}
// Ignore the accessible and its subtree if it was repositioned by means
// of aria-owns.
if (child && child->IsRelocated()) {
*aSkipSubtree = true;
return nullptr;
}
return child;
}
nsIContent*
TreeWalker::Next(ChildrenIterator* aIter, Accessible** aAccesible,
bool* aSkipSubtree)
{
nsIContent* childEl = aIter->mDOMIter.GetNextChild();
if (!aAccesible)
return childEl;
*aAccesible = nullptr;
*aSkipSubtree = false;
if (childEl) {
Accessible* accessible = mFlags & eWalkCache ?
mDoc->GetAccessible(childEl) :
GetAccService()->GetOrCreateAccessible(childEl, mContext, aSkipSubtree);
// Ignore the accessible and its subtree if it was repositioned by means of
// aria-owns.
if (accessible) {
if (accessible->IsRelocated()) {
*aSkipSubtree = true;
} else {
*aAccesible = accessible;
}
}
return childEl;
}
// At last iterate over ARIA owned children.
Accessible* parent = mDoc->GetAccessible(aIter->mDOMIter.Parent());
if (parent) {
Accessible* child = mDoc->ARIAOwnedAt(parent, aIter->mARIAOwnsIdx++);
if (child) {
*aAccesible = child;
return child->GetContent();
}
}
return nullptr;
}