C++ ContainerNode::shadowHost方法代码示例

void HTMLStyleElement::registerWithScopingNode(bool scoped)
{
    // Note: We cannot rely on the 'scoped' element already being present when this method is invoked.
    // Therefore we cannot rely on scoped()!
    ASSERT(m_scopedStyleRegistrationState == NotRegistered);
    ASSERT(inDocument());
    if (m_scopedStyleRegistrationState != NotRegistered)
        return;

    ContainerNode* scope = scoped ? parentNode() : containingShadowRoot();
    if (!scope)
        return;
    if (!scope->isElementNode() && !scope->isShadowRoot()) {
        // DocumentFragment nodes should never be inDocument,
        // <style> should not be a child of Document, PI or some such.
        ASSERT_NOT_REACHED();
        return;
    }
    scope->registerScopedHTMLStyleChild();
    if (scope->isShadowRoot())
        scope->shadowHost()->setNeedsStyleRecalc();
    else
        scope->setNeedsStyleRecalc();
    if (inDocument() && !document()->parsing() && document()->renderer())
        document()->styleResolverChanged(DeferRecalcStyle);

    m_scopedStyleRegistrationState = scoped ? RegisteredAsScoped : RegisteredInShadowRoot;
}

NodeRenderingContext::NodeRenderingContext(Node* node)
    : m_location(LocationNotInTree)
    , m_phase(AttachStraight)
    , m_node(node)
    , m_parentNodeForRenderingAndStyle(0)
    , m_visualParentShadowRoot(0)
    , m_includer(0)
    , m_style(0)
    , m_parentFlowRenderer(0)
{
    ContainerNode* parent = m_node->parentOrHostNode();
    if (!parent)
        return;

    if (parent->isShadowRoot()) {
        m_location = LocationShadowChild;
        m_parentNodeForRenderingAndStyle = parent->shadowHost();
        return;
    }

    m_location = LocationLightChild;

    if (parent->isElementNode()) {
        m_visualParentShadowRoot = toElement(parent)->shadowRoot();

        if (m_visualParentShadowRoot) {
            if ((m_includer = m_visualParentShadowRoot->includerFor(m_node))
                    && m_visualParentShadowRoot->isInclusionSelectorActive()) {
                m_phase = AttachContentForwarded;
                m_parentNodeForRenderingAndStyle = NodeRenderingContext(m_includer).parentNodeForRenderingAndStyle();
                return;
            }

            m_phase = AttachContentLight;
            m_parentNodeForRenderingAndStyle = parent;
            return;
        }

        if (parent->isContentElement()) {
            HTMLContentElement* shadowContentElement = toHTMLContentElement(parent);
            if (!shadowContentElement->hasInclusion()) {
                m_phase = AttachContentFallback;
                m_parentNodeForRenderingAndStyle = NodeRenderingContext(parent).parentNodeForRenderingAndStyle();
                return;
            }
        }
    }

    m_parentNodeForRenderingAndStyle = parent;
}

void VisibleSelection::adjustSelectionToAvoidCrossingEditingBoundaries()
{
    if (m_base.isNull() || m_start.isNull() || m_end.isNull())
        return;

    ContainerNode* baseRoot = highestEditableRoot(m_base);
    ContainerNode* startRoot = highestEditableRoot(m_start);
    ContainerNode* endRoot = highestEditableRoot(m_end);

    Element* baseEditableAncestor = lowestEditableAncestor(m_base.containerNode());

    // The base, start and end are all in the same region.  No adjustment necessary.
    if (baseRoot == startRoot && baseRoot == endRoot)
        return;

    // The selection is based in editable content.
    if (baseRoot) {
        // If the start is outside the base's editable root, cap it at the start of that root.
        // If the start is in non-editable content that is inside the base's editable root, put it
        // at the first editable position after start inside the base's editable root.
        if (startRoot != baseRoot) {
            VisiblePosition first = firstEditableVisiblePositionAfterPositionInRoot(m_start, baseRoot);
            m_start = first.deepEquivalent();
            if (m_start.isNull()) {
                ASSERT_NOT_REACHED();
                m_start = m_end;
            }
        }
        // If the end is outside the base's editable root, cap it at the end of that root.
        // If the end is in non-editable content that is inside the base's root, put it
        // at the last editable position before the end inside the base's root.
        if (endRoot != baseRoot) {
            VisiblePosition last = lastEditableVisiblePositionBeforePositionInRoot(m_end, baseRoot);
            m_end = last.deepEquivalent();
            if (m_end.isNull())
                m_end = m_start;
        }
    // The selection is based in non-editable content.
    } else {
        // FIXME: Non-editable pieces inside editable content should be atomic, in the same way that editable
        // pieces in non-editable content are atomic.

        // The selection ends in editable content or non-editable content inside a different editable ancestor,
        // move backward until non-editable content inside the same lowest editable ancestor is reached.
        Element* endEditableAncestor = lowestEditableAncestor(m_end.containerNode());
        if (endRoot || endEditableAncestor != baseEditableAncestor) {

            Position p = previousVisuallyDistinctCandidate(m_end);
            Element* shadowAncestor = endRoot ? endRoot->shadowHost() : 0;
            if (p.isNull() && shadowAncestor)
                p = positionAfterNode(shadowAncestor);
            while (p.isNotNull() && !(lowestEditableAncestor(p.containerNode()) == baseEditableAncestor && !isEditablePosition(p))) {
                Element* root = editableRootForPosition(p);
                shadowAncestor = root ? root->shadowHost() : 0;
                p = isAtomicNode(p.containerNode()) ? positionInParentBeforeNode(*p.containerNode()) : previousVisuallyDistinctCandidate(p);
                if (p.isNull() && shadowAncestor)
                    p = positionAfterNode(shadowAncestor);
            }
            VisiblePosition previous(p);

            if (previous.isNull()) {
                // The selection crosses an Editing boundary.  This is a
                // programmer error in the editing code.  Happy debugging!
                ASSERT_NOT_REACHED();
                m_base = Position();
                m_extent = Position();
                validate();
                return;
            }
            m_end = previous.deepEquivalent();
        }

        // The selection starts in editable content or non-editable content inside a different editable ancestor,
        // move forward until non-editable content inside the same lowest editable ancestor is reached.
        Element* startEditableAncestor = lowestEditableAncestor(m_start.containerNode());
        if (startRoot || startEditableAncestor != baseEditableAncestor) {
            Position p = nextVisuallyDistinctCandidate(m_start);
            Element* shadowAncestor = startRoot ? startRoot->shadowHost() : 0;
            if (p.isNull() && shadowAncestor)
                p = positionBeforeNode(shadowAncestor);
            while (p.isNotNull() && !(lowestEditableAncestor(p.containerNode()) == baseEditableAncestor && !isEditablePosition(p))) {
                Element* root = editableRootForPosition(p);
                shadowAncestor = root ? root->shadowHost() : 0;
                p = isAtomicNode(p.containerNode()) ? positionInParentAfterNode(*p.containerNode()) : nextVisuallyDistinctCandidate(p);
                if (p.isNull() && shadowAncestor)
                    p = positionBeforeNode(shadowAncestor);
            }
            VisiblePosition next(p);

            if (next.isNull()) {
                // The selection crosses an Editing boundary.  This is a
                // programmer error in the editing code.  Happy debugging!
                ASSERT_NOT_REACHED();
                m_base = Position();
                m_extent = Position();
                validate();
                return;
            }
            m_start = next.deepEquivalent();
        }
//.........这里部分代码省略.........