C++ RenderStyle::contentData方法代码示例

void PseudoElement::attach(const AttachContext& context)
{
    ASSERT(!renderer());

    Element::attach(context);

    RenderObject* renderer = this->renderer();
    if (!renderer)
        return;
    RenderStyle* style = renderer->style();
    if (style->hasFlowFrom())
        return;
    if (style->styleType() != BEFORE && style->styleType() != AFTER)
        return;
    ASSERT(style->contentData());

    for (const ContentData* content = style->contentData(); content; content = content->next()) {
        RenderObject* child = content->createRenderer(document(), style);
        if (renderer->isChildAllowed(child, style)) {
            renderer->addChild(child);
            if (child->isQuote())
                toRenderQuote(child)->attachQuote();
        } else
            child->destroy();
    }
}

void PseudoElement::didAttachRenderers()
{
    RenderObject* renderer = this->renderer();
    if (!renderer || !renderer->style()->regionThread().isEmpty())
        return;

    RenderStyle* style = renderer->style();
    ASSERT(style->contentData());

    for (const ContentData* content = style->contentData(); content; content = content->next()) {
        RenderObject* child = content->createRenderer(document(), style);
        if (renderer->isChildAllowed(child, style)) {
            renderer->addChild(child);
            if (child->isQuote())
                toRenderQuote(child)->attachQuote();
        } else
            child->destroy();
    }
}

void RenderContainer::updatePseudoChild(RenderStyle::PseudoId type, RenderObject* child)
{
    // In CSS2, before/after pseudo-content cannot nest.  Check this first.
    if (style()->styleType() == RenderStyle::BEFORE || style()->styleType() == RenderStyle::AFTER)
        return;
    
    RenderStyle* pseudo = getPseudoStyle(type);

    // Whether or not we currently have generated content attached.
    bool oldContentPresent = child && (child->style()->styleType() == type);

    // Whether or not we now want generated content.  
    bool newContentWanted = pseudo && pseudo->display() != NONE;

    // For <q><p/></q>, if this object is the inline continuation of the <q>, we only want to generate
    // :after content and not :before content.
    if (type == RenderStyle::BEFORE && isInlineContinuation())
        newContentWanted = false;

    // Similarly, if we're the beginning of a <q>, and there's an inline continuation for our object,
    // then we don't generate the :after content.
    if (type == RenderStyle::AFTER && isRenderInline() && continuation())
        newContentWanted = false;
    
    // If we don't want generated content any longer, or if we have generated content, but it's no longer
    // identical to the new content data we want to build render objects for, then we nuke all
    // of the old generated content.
    if (!newContentWanted ||
        (oldContentPresent && !child->style()->contentDataEquivalent(pseudo))) {
        // Nuke the child. 
        if (child && child->style()->styleType() == type) {
            oldContentPresent = false;
            removeChild(child);
            child = (type == RenderStyle::BEFORE) ? firstChild() : lastChild();
        }
    }

    // If we have no pseudo-style or if the pseudo's display type is NONE, then we
    // have no generated content and can now return.
    if (!newContentWanted)
        return;

    if (isInlineFlow() && pseudo->display() != INLINE)
        // According to the CSS2 spec (the end of section 12.1), the only allowed
        // display values for the pseudo style are NONE and INLINE.  Since we already
        // determined that the pseudo is not display NONE, any display other than
        // inline should be mutated to INLINE.
        pseudo->setDisplay(INLINE);
    
    if (oldContentPresent) {
        if (child && child->style()->styleType() == type) {
            // We have generated content present still.  We want to walk this content and update our
            // style information with the new pseudo style.
            child->setStyle(pseudo);

            // Note that if we ever support additional types of generated content (which should be way off
            // in the future), this code will need to be patched.
            for (RenderObject* genChild = child->firstChild(); genChild; genChild = genChild->nextSibling()) {
                if (genChild->isText())
                    // Generated text content is a child whose style also needs to be set to the pseudo
                    // style.
                    genChild->setStyle(pseudo);
                else {
                    // Images get an empty style that inherits from the pseudo.
                    RenderStyle* style = new (renderArena()) RenderStyle();
                    style->inheritFrom(pseudo);
                    genChild->setStyle(style);
                }
            }
        }
        return; // We've updated the generated content. That's all we needed to do.
    }
    
    RenderObject* insertBefore = (type == RenderStyle::BEFORE) ? child : 0;

    // Generated content consists of a single container that houses multiple children (specified
    // by the content property).  This pseudo container gets the pseudo style set on it.
    RenderObject* pseudoContainer = 0;
    
    // Now walk our list of generated content and create render objects for every type
    // we encounter.
    for (ContentData* contentData = pseudo->contentData();
         contentData; contentData = contentData->_nextContent) {
        if (!pseudoContainer)
            pseudoContainer = RenderFlow::createAnonymousFlow(document(), pseudo); /* anonymous box */
        
        if (contentData->contentType() == CONTENT_TEXT)
        {
            RenderText* t = new (renderArena()) RenderTextFragment(document() /*anonymous object */, contentData->contentText());
            t->setStyle(pseudo);
            pseudoContainer->addChild(t);
        }
        else if (contentData->contentType() == CONTENT_OBJECT)
        {
            RenderImage* img = new (renderArena()) RenderImage(document()); /* Anonymous object */
            RenderStyle* style = new (renderArena()) RenderStyle();
            style->inheritFrom(pseudo);
            img->setStyle(style);
            img->setContentObject(contentData->contentObject());
            pseudoContainer->addChild(img);
//.........这里部分代码省略.........