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

void LayoutRubyBase::moveBlockChildren(LayoutRubyBase* toBase, LayoutObject* beforeChild)
{
    ASSERT(!childrenInline());
    ASSERT_ARG(toBase, toBase);

    if (!firstChild())
        return;

    if (toBase->childrenInline())
        toBase->makeChildrenNonInline();

    // If an anonymous block would be put next to another such block, then merge those.
    LayoutObject* firstChildHere = firstChild();
    LayoutObject* lastChildThere = toBase->lastChild();
    if (firstChildHere->isAnonymousBlock() && firstChildHere->childrenInline()
        && lastChildThere && lastChildThere->isAnonymousBlock() && lastChildThere->childrenInline()) {
        LayoutBlock* anonBlockHere = toLayoutBlock(firstChildHere);
        LayoutBlock* anonBlockThere = toLayoutBlock(lastChildThere);
        anonBlockHere->moveAllChildrenTo(anonBlockThere, anonBlockThere->children());
        anonBlockHere->deleteLineBoxTree();
        anonBlockHere->destroy();
    }
    // Move all remaining children normally.
    moveChildrenTo(toBase, firstChild(), beforeChild);
}

void LayoutRubyBase::moveInlineChildren(LayoutRubyBase* toBase, LayoutObject* beforeChild)
{
    ASSERT(childrenInline());
    ASSERT_ARG(toBase, toBase);

    if (!firstChild())
        return;

    LayoutBlock* toBlock;
    if (toBase->childrenInline()) {
        // The standard and easy case: move the children into the target base
        toBlock = toBase;
    } else {
        // We need to wrap the inline objects into an anonymous block.
        // If toBase has a suitable block, we re-use it, otherwise create a new one.
        LayoutObject* lastChild = toBase->lastChild();
        if (lastChild && lastChild->isAnonymousBlock() && lastChild->childrenInline()) {
            toBlock = toLayoutBlock(lastChild);
        } else {
            toBlock = toBase->createAnonymousBlock();
            toBase->children()->appendChildNode(toBase, toBlock);
        }
    }
    // Move our inline children into the target block we determined above.
    moveChildrenTo(toBlock, firstChild(), beforeChild);
}

bool Text::textLayoutObjectIsNeeded(const ComputedStyle& style, const LayoutObject& parent)
{
    if (!parent.canHaveChildren())
        return false;

    if (isEditingText())
        return true;

    if (!length())
        return false;

    if (style.display() == NONE)
        return false;

    if (!containsOnlyWhitespace())
        return true;

    if (!canHaveWhitespaceChildren(parent, this))
        return false;

    // pre-wrap in SVG never makes layoutObject.
    if (style.whiteSpace() == PRE_WRAP && parent.isSVG())
        return false;

    // pre/pre-wrap/-bb-pre-wrap-text/pre-line always make layoutObjects.
    if (style.preserveNewline())
        return true;

    // childNeedsDistributionRecalc() here is rare, only happens JS calling surroundContents() etc. from DOMNodeInsertedIntoDocument etc.
    if (document().childNeedsDistributionRecalc())
        return true;

    const LayoutObject* prev = LayoutTreeBuilderTraversal::previousSiblingLayoutObject(*this);
    if (prev && prev->isBR()) // <span><br/> <br/></span>
        return false;

    if (parent.isLayoutInline()) {
        // <span><div/> <div/></span>
        if (prev && !prev->isInline() && !prev->isOutOfFlowPositioned())
            return false;
    } else {
        if (parent.isLayoutBlock() && !parent.childrenInline() && (!prev || !prev->isInline()))
            return false;

        // Avoiding creation of a layoutObject for the text node is a non-essential memory optimization.
        // So to avoid blowing up on very wide DOMs, we limit the number of siblings to visit.
        unsigned maxSiblingsToVisit = 50;

        LayoutObject* first = parent.slowFirstChild();
        while (first && first->isFloatingOrOutOfFlowPositioned() && maxSiblingsToVisit--)
            first = first->nextSibling();
        if (!first || first == layoutObject() || LayoutTreeBuilderTraversal::nextSiblingLayoutObject(*this) == first) {
            // Whitespace at the start of a block just goes away.  Don't even
            // make a layout object for this text.
            return false;
        }
    }
    return true;
}