C++ LayoutObject::generatingNode方法代码示例

static bool planCounter(LayoutObject& object, const AtomicString& identifier, bool& isReset, int& value)
{
    // Real text nodes don't have their own style so they can't have counters.
    // We can't even look at their styles or we'll see extra resets and increments!
    if (object.isText() && !object.isBR())
        return false;
    Node* generatingNode = object.generatingNode();
    // We must have a generating node or else we cannot have a counter.
    if (!generatingNode)
        return false;
    const ComputedStyle& style = object.styleRef();

    switch (style.styleType()) {
    case NOPSEUDO:
        // Sometimes nodes have more then one layoutObject. Only the first one gets the counter
        // LayoutTests/http/tests/css/counter-crash.html
        if (generatingNode->layoutObject() != &object)
            return false;
        break;
    case BEFORE:
    case AFTER:
        break;
    default:
        return false; // Counters are forbidden from all other pseudo elements.
    }

    const CounterDirectives directives = style.getCounterDirectives(identifier);
    if (directives.isDefined()) {
        value = directives.combinedValue();
        isReset = directives.isReset();
        return true;
    }

    if (identifier == "list-item") {
        if (object.isListItem()) {
            if (toLayoutListItem(object).hasExplicitValue()) {
                value = toLayoutListItem(object).explicitValue();
                isReset = true;
                return true;
            }
            value = 1;
            isReset = false;
            return true;
        }
        if (Node* e = object.node()) {
            if (isHTMLOListElement(*e)) {
                value = toHTMLOListElement(e)->start();
                isReset = true;
                return true;
            }
            if (isHTMLUListElement(*e) || isHTMLMenuElement(*e) || isHTMLDirectoryElement(*e)) {
                value = 0;
                isReset = true;
                return true;
            }
        }
    }

    return false;
}

void LayoutCounter::layoutObjectStyleChanged(LayoutObject& layoutObject, const ComputedStyle* oldStyle, const ComputedStyle& newStyle)
{
    Node* node = layoutObject.generatingNode();
    if (!node || node->needsAttach())
        return; // cannot have generated content or if it can have, it will be handled during attaching
    const CounterDirectiveMap* oldCounterDirectives = oldStyle ? oldStyle->counterDirectives() : 0;
    const CounterDirectiveMap* newCounterDirectives = newStyle.counterDirectives();
    if (oldCounterDirectives) {
        if (newCounterDirectives) {
            CounterDirectiveMap::const_iterator newMapEnd = newCounterDirectives->end();
            CounterDirectiveMap::const_iterator oldMapEnd = oldCounterDirectives->end();
            for (CounterDirectiveMap::const_iterator it = newCounterDirectives->begin(); it != newMapEnd; ++it) {
                CounterDirectiveMap::const_iterator oldMapIt = oldCounterDirectives->find(it->key);
                if (oldMapIt != oldMapEnd) {
                    if (oldMapIt->value == it->value)
                        continue;
                    LayoutCounter::destroyCounterNode(layoutObject, it->key);
                }
                // We must create this node here, because the changed node may be a node with no display such as
                // as those created by the increment or reset directives and the re-layout that will happen will
                // not catch the change if the node had no children.
                makeCounterNode(layoutObject, it->key, false);
            }
            // Destroying old counters that do not exist in the new counterDirective map.
            for (CounterDirectiveMap::const_iterator it = oldCounterDirectives->begin(); it !=oldMapEnd; ++it) {
                if (!newCounterDirectives->contains(it->key))
                    LayoutCounter::destroyCounterNode(layoutObject, it->key);
            }
        } else {
            if (layoutObject.hasCounterNodeMap())
                LayoutCounter::destroyCounterNodes(layoutObject);
        }
    } else if (newCounterDirectives) {
        if (layoutObject.hasCounterNodeMap())
            LayoutCounter::destroyCounterNodes(layoutObject);
        CounterDirectiveMap::const_iterator newMapEnd = newCounterDirectives->end();
        for (CounterDirectiveMap::const_iterator it = newCounterDirectives->begin(); it != newMapEnd; ++it) {
            // We must create this node here, because the added node may be a node with no display such as
            // as those created by the increment or reset directives and the re-layout that will happen will
            // not catch the change if the node had no children.
            makeCounterNode(layoutObject, it->key, false);
        }
    }
}