C++ LayoutBlock::deleteLineBoxTree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 LayoutRubyRun::removeChild(LayoutObject* child)
{
    // If the child is a ruby text, then merge the ruby base with the base of
    // the right sibling run, if possible.
    if (!beingDestroyed() && !documentBeingDestroyed() && child->isRubyText()) {
        LayoutRubyBase* base = rubyBase();
        LayoutObject* rightNeighbour = nextSibling();
        if (base && rightNeighbour && rightNeighbour->isRubyRun()) {
            // Ruby run without a base can happen only at the first run.
            LayoutRubyRun* rightRun = toLayoutRubyRun(rightNeighbour);
            if (rightRun->hasRubyBase()) {
                LayoutRubyBase* rightBase = rightRun->rubyBaseSafe();
                // Collect all children in a single base, then swap the bases.
                rightBase->moveChildren(base);
                moveChildTo(rightRun, base);
                rightRun->moveChildTo(this, rightBase);
                // The now empty ruby base will be removed below.
                ASSERT(!rubyBase()->firstChild());
            }
        }
    }

    LayoutBlockFlow::removeChild(child);

    if (!beingDestroyed() && !documentBeingDestroyed()) {
        // Check if our base (if any) is now empty. If so, destroy it.
        LayoutBlock* base = rubyBase();
        if (base && !base->firstChild()) {
            LayoutBlockFlow::removeChild(base);
            base->deleteLineBoxTree();
            base->destroy();
        }

        // If any of the above leaves the run empty, destroy it as well.
        if (!hasRubyText() && !hasRubyBase()) {
            deleteLineBoxTree();
            destroy();
        }
    }
}

LayoutObject* LayoutFullScreen::wrapLayoutObject(LayoutObject* object, LayoutObject* parent, Document* document)
{
    // FIXME: We should not modify the structure of the layout tree during
    // layout. crbug.com/370459
    DeprecatedDisableModifyLayoutTreeStructureAsserts disabler;

    LayoutFullScreen* fullscreenLayoutObject = LayoutFullScreen::createAnonymous(document);
    fullscreenLayoutObject->updateStyle();
    if (parent && !parent->isChildAllowed(fullscreenLayoutObject, fullscreenLayoutObject->styleRef())) {
        fullscreenLayoutObject->destroy();
        return nullptr;
    }
    if (object) {
        // |object->parent()| can be null if the object is not yet attached
        // to |parent|.
        if (LayoutObject* parent = object->parent()) {
            LayoutBlock* containingBlock = object->containingBlock();
            ASSERT(containingBlock);
            // Since we are moving the |object| to a new parent |fullscreenLayoutObject|,
            // the line box tree underneath our |containingBlock| is not longer valid.
            containingBlock->deleteLineBoxTree();

            parent->addChild(fullscreenLayoutObject, object);
            object->remove();

            // Always just do a full layout to ensure that line boxes get deleted properly.
            // Because objects moved from |parent| to |fullscreenLayoutObject|, we want to
            // make new line boxes instead of leaving the old ones around.
            parent->setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation(LayoutInvalidationReason::Fullscreen);
            containingBlock->setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation(LayoutInvalidationReason::Fullscreen);
        }
        fullscreenLayoutObject->addChild(object);
        fullscreenLayoutObject->setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation(LayoutInvalidationReason::Fullscreen);
    }

    ASSERT(document);
    Fullscreen::from(*document).setFullScreenLayoutObject(fullscreenLayoutObject);
    return fullscreenLayoutObject;
}