C++ ProxyAccessible::ChildAt方法代码示例

bool
DocAccessibleParent::AddChildDoc(DocAccessibleParent* aChildDoc,
                                 uint64_t aParentID, bool aCreating)
{
  // We do not use GetAccessible here because we want to be sure to not get the
  // document it self.
  ProxyEntry* e = mAccessibles.GetEntry(aParentID);
  if (!e)
    return false;

  ProxyAccessible* outerDoc = e->mProxy;
  MOZ_ASSERT(outerDoc);

  // OuterDocAccessibles are expected to only have a document as a child.
  // However for compatibility we tolerate replacing one document with another
  // here.
  if (outerDoc->ChildrenCount() > 1 ||
      (outerDoc->ChildrenCount() == 1 && !outerDoc->ChildAt(0)->IsDoc())) {
    return false;
  }

  aChildDoc->mParent = outerDoc;
  outerDoc->SetChildDoc(aChildDoc);
  mChildDocs.AppendElement(aChildDoc);
  aChildDoc->mParentDoc = this;

  if (aCreating) {
    ProxyCreated(aChildDoc, Interfaces::DOCUMENT | Interfaces::HYPERTEXT);
  }

  return true;
}

ipc::IPCResult
DocAccessibleParent::AddChildDoc(DocAccessibleParent* aChildDoc,
                                 uint64_t aParentID, bool aCreating)
{
  // We do not use GetAccessible here because we want to be sure to not get the
  // document it self.
  ProxyEntry* e = mAccessibles.GetEntry(aParentID);
  if (!e) {
    return IPC_FAIL(this, "binding to nonexistant proxy!");
  }

  ProxyAccessible* outerDoc = e->mProxy;
  MOZ_ASSERT(outerDoc);

  // OuterDocAccessibles are expected to only have a document as a child.
  // However for compatibility we tolerate replacing one document with another
  // here.
  if (outerDoc->ChildrenCount() > 1 ||
      (outerDoc->ChildrenCount() == 1 && !outerDoc->ChildAt(0)->IsDoc())) {
    return IPC_FAIL(this, "binding to proxy that can't be a outerDoc!");
  }

  aChildDoc->SetParent(outerDoc);
  outerDoc->SetChildDoc(aChildDoc);
  mChildDocs.AppendElement(aChildDoc->mActorID);
  aChildDoc->mParentDoc = mActorID;

  if (aCreating) {
    ProxyCreated(aChildDoc, Interfaces::DOCUMENT | Interfaces::HYPERTEXT);
  }

  return IPC_OK();
}

bool
DocAccessibleParent::RecvShowEvent(const ShowEventData& aData,
                                   const bool& aFromUser)
{
  if (mShutdown)
    return true;

  MOZ_DIAGNOSTIC_ASSERT(CheckDocTree());

  if (aData.NewTree().IsEmpty()) {
    NS_ERROR("no children being added");
    return false;
  }

  ProxyAccessible* parent = GetAccessible(aData.ID());

  // XXX This should really never happen, but sometimes we fail to fire the
  // required show events.
  if (!parent) {
    NS_ERROR("adding child to unknown accessible");
    return true;
  }

  uint32_t newChildIdx = aData.Idx();
  if (newChildIdx > parent->ChildrenCount()) {
    NS_ERROR("invalid index to add child at");
    return true;
  }

  uint32_t consumed = AddSubtree(parent, aData.NewTree(), 0, newChildIdx);
  MOZ_ASSERT(consumed == aData.NewTree().Length());

  // XXX This shouldn't happen, but if we failed to add children then the below
  // is pointless and can crash.
  if (!consumed) {
    return true;
  }

#ifdef DEBUG
  for (uint32_t i = 0; i < consumed; i++) {
    uint64_t id = aData.NewTree()[i].ID();
    MOZ_ASSERT(mAccessibles.GetEntry(id));
  }
#endif

  MOZ_DIAGNOSTIC_ASSERT(CheckDocTree());

  ProxyAccessible* target = parent->ChildAt(newChildIdx);
  ProxyShowHideEvent(target, parent, true, aFromUser);

  if (!nsCoreUtils::AccEventObserversExist()) {
    return true;
  }

  uint32_t type = nsIAccessibleEvent::EVENT_SHOW;
  xpcAccessibleGeneric* xpcAcc = GetXPCAccessible(target);
  xpcAccessibleDocument* doc = GetAccService()->GetXPCDocument(this);
  nsIDOMNode* node = nullptr;
  RefPtr<xpcAccEvent> event = new xpcAccEvent(type, xpcAcc, doc, node,
                                              aFromUser);
  nsCoreUtils::DispatchAccEvent(Move(event));

  return true;
}