C++ Accessible::CurrentItem方法代码示例

void
FocusManager::ProcessDOMFocus(nsINode* aTarget)
{
#ifdef A11Y_LOG
  if (logging::IsEnabled(logging::eFocus))
    logging::FocusNotificationTarget("process DOM focus", "Target", aTarget);
#endif

  DocAccessible* document =
    GetAccService()->GetDocAccessible(aTarget->OwnerDoc());
  if (!document)
    return;

  Accessible* target = document->GetAccessibleEvenIfNotInMapOrContainer(aTarget);
  if (target) {
    // Check if still focused. Otherwise we can end up with storing the active
    // item for control that isn't focused anymore.
    nsINode* focusedNode = FocusedDOMNode();
    if (!focusedNode)
      return;

    Accessible* DOMFocus =
      document->GetAccessibleEvenIfNotInMapOrContainer(focusedNode);
    if (target != DOMFocus)
      return;

    Accessible* activeItem = target->CurrentItem();
    if (activeItem) {
      mActiveItem = activeItem;
      target = activeItem;
    }

    DispatchFocusEvent(document, target);
  }
}

// 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.........

void
FocusManager::ProcessFocusEvent(AccEvent* aEvent)
{
  NS_PRECONDITION(aEvent->GetEventType() == nsIAccessibleEvent::EVENT_FOCUS,
                  "Focus event is expected!");

  // Emit focus event if event target is the active item. Otherwise then check
  // if it's still focused and then update active item and emit focus event.
  Accessible* target = aEvent->GetAccessible();
  if (target != mActiveItem) {

    // Check if still focused. Otherwise we can end up with storing the active
    // item for control that isn't focused anymore.
    DocAccessible* document = aEvent->GetDocAccessible();
    nsINode* focusedNode = FocusedDOMNode();
    if (!focusedNode)
      return;

    Accessible* DOMFocus =
      document->GetAccessibleEvenIfNotInMapOrContainer(focusedNode);
    if (target != DOMFocus)
      return;

    Accessible* activeItem = target->CurrentItem();
    if (activeItem) {
      mActiveItem = activeItem;
      target = activeItem;
    }
  }

  // Fire menu start/end events for ARIA menus.
  if (target->IsARIARole(nsGkAtoms::menuitem)) {
    // The focus was moved into menu.
    Accessible* ARIAMenubar = nullptr;
    for (Accessible* parent = target->Parent(); parent; parent = parent->Parent()) {
      if (parent->IsARIARole(nsGkAtoms::menubar)) {
        ARIAMenubar = parent;
        break;
      }

      // Go up in the parent chain of the menu hierarchy.
      if (!parent->IsARIARole(nsGkAtoms::menuitem) &&
          !parent->IsARIARole(nsGkAtoms::menu)) {
        break;
      }
    }

    if (ARIAMenubar != mActiveARIAMenubar) {
      // Leaving ARIA menu. Fire menu_end event on current menubar.
      if (mActiveARIAMenubar) {
        RefPtr<AccEvent> menuEndEvent =
          new AccEvent(nsIAccessibleEvent::EVENT_MENU_END, mActiveARIAMenubar,
                       aEvent->FromUserInput());
        nsEventShell::FireEvent(menuEndEvent);
      }

      mActiveARIAMenubar = ARIAMenubar;

      // Entering ARIA menu. Fire menu_start event.
      if (mActiveARIAMenubar) {
        RefPtr<AccEvent> menuStartEvent =
          new AccEvent(nsIAccessibleEvent::EVENT_MENU_START,
                       mActiveARIAMenubar, aEvent->FromUserInput());
        nsEventShell::FireEvent(menuStartEvent);
      }
    }
  } else if (mActiveARIAMenubar) {
    // Focus left a menu. Fire menu_end event.
    RefPtr<AccEvent> menuEndEvent =
      new AccEvent(nsIAccessibleEvent::EVENT_MENU_END, mActiveARIAMenubar,
                   aEvent->FromUserInput());
    nsEventShell::FireEvent(menuEndEvent);

    mActiveARIAMenubar = nullptr;
  }

#ifdef A11Y_LOG
  if (logging::IsEnabled(logging::eFocus))
    logging::FocusNotificationTarget("fire focus event", "Target", target);
#endif

  // Reset cached caret value. The cache will be updated upon processing the
  // next caret move event. This ensures that we will return the correct caret
  // offset before the caret move event is handled.
  SelectionMgr()->ResetCaretOffset();

  RefPtr<AccEvent> focusEvent =
    new AccEvent(nsIAccessibleEvent::EVENT_FOCUS, target, aEvent->FromUserInput());
  nsEventShell::FireEvent(focusEvent);

  // Fire scrolling_start event when the document receives the focus if it has
  // an anchor jump. If an accessible within the document receive the focus
  // then null out the anchor jump because it no longer applies.
  DocAccessible* targetDocument = target->Document();
  Accessible* anchorJump = targetDocument->AnchorJump();
  if (anchorJump) {
    if (target == targetDocument) {
      // XXX: bug 625699, note in some cases the node could go away before we
      // we receive focus event, for example if the node is removed from DOM.
      nsEventShell::FireEvent(nsIAccessibleEvent::EVENT_SCROLLING_START,
//.........这里部分代码省略.........

void
FocusManager::ProcessFocusEvent(AccEvent* aEvent)
{
  NS_PRECONDITION(aEvent->GetEventType() == nsIAccessibleEvent::EVENT_FOCUS,
                  "Focus event is expected!");

  // Emit focus event if event target is the active item. Otherwise then check
  // if it's still focused and then update active item and emit focus event.
  Accessible* target = aEvent->GetAccessible();
  if (target != mActiveItem) {

    // Check if still focused. Otherwise we can end up with storing the active
    // item for control that isn't focused anymore.
    DocAccessible* document = aEvent->GetDocAccessible();
    nsINode* focusedNode = FocusedDOMNode();
    if (!focusedNode)
      return;

    Accessible* DOMFocus =
      document->GetAccessibleEvenIfNotInMapOrContainer(focusedNode);
    if (target != DOMFocus)
      return;

    Accessible* activeItem = target->CurrentItem();
    if (activeItem) {
      mActiveItem = activeItem;
      target = activeItem;
    }
  }

  // Fire menu start/end events for ARIA menus.
  if (target->IsARIARole(nsGkAtoms::menuitem)) {
    // The focus was moved into menu.
    bool tryOwnsParent = true;
    Accessible* ARIAMenubar = nullptr;
    Accessible* child = target;
    Accessible* parent = child->Parent();
    while (parent) {
      nsRoleMapEntry* roleMap = parent->ARIARoleMap();
      if (roleMap) {
        if (roleMap->Is(nsGkAtoms::menubar)) {
          ARIAMenubar = parent;
          break;
        }

        // Go up in the parent chain of the menu hierarchy.
        if (roleMap->Is(nsGkAtoms::menuitem) || roleMap->Is(nsGkAtoms::menu)) {
          child = parent;
          parent = child->Parent();
          tryOwnsParent = true;
          continue;
        }
      }

      // If no required context role then check aria-owns relation.
      if (!tryOwnsParent)
        break;

      RelatedAccIterator iter(child->Document(), child->GetContent(),
                              nsGkAtoms::aria_owns);
      parent = iter.Next();
      tryOwnsParent = false;
    }

    if (ARIAMenubar != mActiveARIAMenubar) {
      // Leaving ARIA menu. Fire menu_end event on current menubar.
      if (mActiveARIAMenubar) {
        nsRefPtr<AccEvent> menuEndEvent =
          new AccEvent(nsIAccessibleEvent::EVENT_MENU_END, mActiveARIAMenubar,
                       aEvent->FromUserInput());
        nsEventShell::FireEvent(menuEndEvent);
      }

      mActiveARIAMenubar = ARIAMenubar;

      // Entering ARIA menu. Fire menu_start event.
      if (mActiveARIAMenubar) {
        nsRefPtr<AccEvent> menuStartEvent =
          new AccEvent(nsIAccessibleEvent::EVENT_MENU_START,
                       mActiveARIAMenubar, aEvent->FromUserInput());
        nsEventShell::FireEvent(menuStartEvent);
      }
    }
  } else if (mActiveARIAMenubar) {
    // Focus left a menu. Fire menu_end event.
    nsRefPtr<AccEvent> menuEndEvent =
      new AccEvent(nsIAccessibleEvent::EVENT_MENU_END, mActiveARIAMenubar,
                   aEvent->FromUserInput());
    nsEventShell::FireEvent(menuEndEvent);

    mActiveARIAMenubar = nullptr;
  }

#ifdef A11Y_LOG
  if (logging::IsEnabled(logging::eFocus))
    logging::FocusNotificationTarget("fire focus event", "Target", target);
#endif

  nsRefPtr<AccEvent> focusEvent =
    new AccEvent(nsIAccessibleEvent::EVENT_FOCUS, target, aEvent->FromUserInput());
//.........这里部分代码省略.........