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/*
* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
* (C) 1999 Antti Koivisto (koivisto@kde.org)
* (C) 2001 Dirk Mueller (mueller@kde.org)
* Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All
* rights reserved.
* Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
* (http://www.torchmobile.com/)
* Copyright (C) 2011 Google Inc. All rights reserved.
*
* 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.
*
*/
#ifndef LayoutTreeBuilder_h
#define LayoutTreeBuilder_h
#include "core/dom/Document.h"
#include "core/dom/LayoutTreeBuilderTraversal.h"
#include "core/dom/Node.h"
#include "core/dom/Text.h"
#include "core/layout/LayoutObject.h"
#include "wtf/RefPtr.h"
namespace blink {
class ComputedStyle;
template <typename NodeType>
class LayoutTreeBuilder {
STACK_ALLOCATED();
protected:
LayoutTreeBuilder(NodeType& node, LayoutObject* layoutObjectParent)
: m_node(node), m_layoutObjectParent(layoutObjectParent) {
DCHECK(!node.layoutObject());
DCHECK(node.needsAttach());
DCHECK(node.document().inStyleRecalc());
DCHECK(node.inActiveDocument());
}
LayoutObject* nextLayoutObject() const {
DCHECK(m_layoutObjectParent);
// Avoid an O(N^2) walk over the children when reattaching all children of a
// node.
if (m_layoutObjectParent->node() &&
m_layoutObjectParent->node()->needsAttach())
return 0;
return LayoutTreeBuilderTraversal::nextSiblingLayoutObject(*m_node);
}
Member<NodeType> m_node;
LayoutObject* m_layoutObjectParent;
};
class LayoutTreeBuilderForElement : public LayoutTreeBuilder<Element> {
public:
LayoutTreeBuilderForElement(Element&, ComputedStyle*);
void createLayoutObjectIfNeeded() {
if (shouldCreateLayoutObject())
createLayoutObject();
}
private:
LayoutObject* parentLayoutObject() const;
LayoutObject* nextLayoutObject() const;
bool shouldCreateLayoutObject() const;
ComputedStyle& style() const;
void createLayoutObject();
mutable RefPtr<ComputedStyle> m_style;
};
class LayoutTreeBuilderForText : public LayoutTreeBuilder<Text> {
public:
LayoutTreeBuilderForText(Text& text, LayoutObject* layoutParent)
: LayoutTreeBuilder(text, layoutParent) {}
void createLayoutObject();
};
} // namespace blink
#endif
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