render_container.cpp

konqueror3 embedded版本, KDE环境下的当家浏览器的嵌入式版本源码包.

/**
 * This file is part of the html renderer for KDE.
 *
 * Copyright (C) 2001-2003 Lars Knoll ([e-mail])
 *           (C) 2001 Antti Koivisto ([e-mail])
 *           (C) 2000-2003 Dirk Mueller ([e-mail])
 *           (C) 2002-2003 Apple Computer, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 */

//#define DEBUG_LAYOUT

#include "rendering/render_container.h"
#include "rendering/render_table.h"
#include "rendering/render_text.h"
#include "rendering/render_image.h"
#include "rendering/render_canvas.h"
#include "rendering/render_generated.h"
#include "rendering/render_inline.h"
#include "xml/dom_docimpl.h"
#include "css/css_valueimpl.h"

#include <kdebug.h>
#include <assert.h>

using namespace khtml;

RenderContainer::RenderContainer(DOM::NodeImpl* node)
    : RenderObject(node)
{
    m_first = 0;
    m_last = 0;
}

void RenderContainer::detach()
{
    if (continuation())
        continuation()->detach();

    RenderObject* next;
    for(RenderObject* n = m_first; n; n = next ) {
	n->removeFromObjectLists();
        n->setParent(0);
        next = n->nextSibling();
        n->detach();
    }
    m_first = 0;
    m_last = 0;

    RenderObject::detach();
}

void RenderContainer::addChild(RenderObject *newChild, RenderObject *beforeChild)
{
#ifdef DEBUG_LAYOUT
    kdDebug( 6040 ) << this << ": " <<  renderName() << "(RenderObject)::addChild( " << newChild << ": " <<
        newChild->renderName() << ", " << (beforeChild ? beforeChild->renderName() : "0") << " )" << endl;
#endif

    bool needsTable = false;

    if(!newChild->isText() && !newChild->isReplaced()) {
        switch(newChild->style()->display()) {
        case INLINE:
        case BLOCK:
        case LIST_ITEM:
        case RUN_IN:
	case COMPACT:
        case INLINE_BLOCK:
        case TABLE:
        case INLINE_TABLE:
            break;
        case TABLE_COLUMN:
            if ( isTableCol() )
                break;
            // nobreak
        case TABLE_COLUMN_GROUP:
        case TABLE_CAPTION:
        case TABLE_ROW_GROUP:
        case TABLE_HEADER_GROUP:
        case TABLE_FOOTER_GROUP:

            //kdDebug( 6040 ) << "adding section" << endl;
            if ( !isTable() )
                needsTable = true;
            break;
        case TABLE_ROW:
            //kdDebug( 6040 ) << "adding row" << endl;
            if ( !isTableSection() )
                needsTable = true;
            break;
        case TABLE_CELL:
            //kdDebug( 6040 ) << "adding cell" << endl;
            if ( !isTableRow() )
                needsTable = true;
            // I'm not 100% sure this is the best way to fix this, but without this
            // change we recurse infinitely when trying to render the CSS2 test page:
            // http://www.bath.ac.uk/%7Epy8ieh/internet/eviltests/htmlbodyheadrendering2.html.
            if ( isTableCell() && !firstChild() && !newChild->isTableCell() )
                needsTable = false;

            break;
        case NONE:
            // RenderHtml and some others can have display:none
            // KHTMLAssert(false);
            break;
        }
    }

    if ( needsTable ) {
        RenderTable *table;
	RenderObject *last = beforeChild ? beforeChild->previousSibling() : lastChild();
        if ( last && last->isTable() && last->isAnonymous() ) {
            table = static_cast<RenderTable *>(last);
        } else {
	    //kdDebug( 6040 ) << "creating anonymous table, before=" << beforeChild << endl;
            table = new (renderArena()) RenderTable(document() /* is anonymous */);
            RenderStyle *newStyle = new RenderStyle();
            newStyle->inheritFrom(style());
	    newStyle->setDisplay( TABLE );
	    newStyle->setFlowAroundFloats( true );
	    table->setParent( this ); // so it finds the arena
            table->setStyle(newStyle);
	    table->setParent( 0 );
            addChild(table, beforeChild);
        }
        table->addChild(newChild);
    } else {
	// just add it...
	insertChildNode(newChild, beforeChild);
    }
}

RenderObject* RenderContainer::removeChildNode(RenderObject* oldChild)
{
    KHTMLAssert(oldChild->parent() == this);

    // So that we'll get the appropriate dirty bit set (either that a normal flow child got yanked or
    // that a positioned child got yanked).  We also repaint, so that the area exposed when the child
    // disappears gets repainted properly.
    if ( document()->renderer() ) {
        oldChild->setNeedsLayoutAndMinMaxRecalc();
        oldChild->repaint();

        // Keep our layer hierarchy updated.
        oldChild->removeLayers(enclosingLayer());

        // if oldChild is the start or end of the selection, then clear
        // the selection to avoid problems of invalid pointers

        // ### This is not the "proper" solution... ideally the selection
        // ### should be maintained based on DOM Nodes and a Range, which
        // ### gets adjusted appropriately when nodes are deleted/inserted
        // ### near etc. But this at least prevents crashes caused when
        // ### the start or end of the selection is deleted and then
        // ### accessed when the user next selects something.

        if (oldChild->isSelectionBorder()) {
            RenderObject *root = oldChild;
            while (root && root->parent())
                root = root->parent();
            if (root->isCanvas()) {
                static_cast<RenderCanvas*>(root)->clearSelection();
            }
        }
    }

    // remove the child
    if (oldChild->previousSibling())
        oldChild->previousSibling()->setNextSibling(oldChild->nextSibling());
    if (oldChild->nextSibling())
        oldChild->nextSibling()->setPreviousSibling(oldChild->previousSibling());

    if (m_first == oldChild)
        m_first = oldChild->nextSibling();
    if (m_last == oldChild)
        m_last = oldChild->previousSibling();

    oldChild->setPreviousSibling(0);
    oldChild->setNextSibling(0);
    oldChild->setParent(0);

    return oldChild;
}

void RenderContainer::setStyle(RenderStyle* _style)
{
    RenderObject::setStyle(_style);

    // If we are a pseudo-container we need to restyle the children
    if (style()->styleType() == RenderStyle::BEFORE
     || style()->styleType() == RenderStyle::AFTER)
    {
        // ### we could save this call when the change only affected
        // non inherited properties
        RenderStyle *pseudoStyle = new RenderStyle();
        pseudoStyle->inheritFrom(style());
        pseudoStyle->ref();
        RenderObject *child = firstChild();
        while (child != 0)
        {
            child->setStyle(pseudoStyle);
            child = child->nextSibling();
        }
        pseudoStyle->deref();
    }
}

void RenderContainer::updatePseudoChildren()
{
    // In CSS2, before/after pseudo-content cannot nest.  Check this first.
    // Remove when CSS 3 Generated Content becomes Candidate Recommendation
    if (style()->styleType() == RenderStyle::BEFORE
     || style()->styleType() == RenderStyle::AFTER)
        return;

    updatePseudoChild(RenderStyle::BEFORE, firstChild());
    updatePseudoChild(RenderStyle::AFTER, lastChild());
    // updatePseudoChild(RenderStyle::MARKER, marker());
}

void RenderContainer::updatePseudoChild(RenderStyle::PseudoId type, RenderObject* child)
{
    RenderStyle* pseudo = style()->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.