C++ RenderElement::generatingElement方法代码示例

static bool planCounter(RenderElement& renderer, const AtomicString& identifier, bool& isReset, int& value)
{
    // We must have a generating node or else we cannot have a counter.
    Element* generatingElement = renderer.generatingElement();
    if (!generatingElement)
        return false;

    const RenderStyle& style = renderer.style();

    switch (style.styleType()) {
    case NOPSEUDO:
        // Sometimes elements have more then one renderer. Only the first one gets the counter
        // LayoutTests/http/tests/css/counter-crash.html
        if (generatingElement->renderer() != &renderer)
            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 (is<RenderListItem>(renderer)) {
            if (downcast<RenderListItem>(renderer).hasExplicitValue()) {
                value = downcast<RenderListItem>(renderer).explicitValue();
                isReset = true;
                return true;
            }
            value = 1;
            isReset = false;
            return true;
        }
        if (Element* element = renderer.element()) {
            if (is<HTMLOListElement>(*element)) {
                value = downcast<HTMLOListElement>(*element).start();
                isReset = true;
                return true;
            }
            if (element->hasTagName(ulTag) || element->hasTagName(menuTag) || element->hasTagName(dirTag)) {
                value = 0;
                isReset = true;
                return true;
            }
        }
    }

    return false;
}

void RenderCounter::rendererSubtreeAttached(RenderElement& renderer)
{
    if (!renderer.view().hasRenderCounters())
        return;
    Element* element = renderer.element();
    if (element && !element->isPseudoElement())
        element = element->parentElement();
    else
        element = renderer.generatingElement();
    if (element && !element->renderer())
        return; // No need to update if the parent is not attached yet
    for (RenderObject* descendant = &renderer; descendant; descendant = descendant->nextInPreOrder(&renderer)) {
        if (is<RenderElement>(*descendant))
            updateCounters(downcast<RenderElement>(*descendant));
    }
}

void RenderCounter::rendererStyleChanged(RenderElement& renderer, const RenderStyle* oldStyle, const RenderStyle* newStyle)
{
    Element* element = renderer.generatingElement();
    if (!element || !element->renderer())
        return; // cannot have generated content or if it can have, it will be handled during attaching
    const CounterDirectiveMap* newCounterDirectives;
    const CounterDirectiveMap* oldCounterDirectives;
    if (oldStyle && (oldCounterDirectives = oldStyle->counterDirectives())) {
        if (newStyle && (newCounterDirectives = newStyle->counterDirectives())) {
            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;
                    RenderCounter::destroyCounterNode(renderer, 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(renderer, 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))
                    RenderCounter::destroyCounterNode(renderer, it->key);
            }
        } else {
            if (renderer.hasCounterNodeMap())
                RenderCounter::destroyCounterNodes(renderer);
        }
    } else if (newStyle && (newCounterDirectives = newStyle->counterDirectives())) {
        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(renderer, it->key, false);
        }
    }
}