gecko/accessible/src/base/TreeWalker.h

80 lines
1.9 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_a11y_TreeWalker_h_
#define mozilla_a11y_TreeWalker_h_
#include <stdint.h>
class nsIContent;
namespace mozilla {
namespace a11y {
class Accessible;
class DocAccessible;
struct WalkState;
/**
* This class is used to walk the DOM tree to create accessible tree.
*/
class TreeWalker
{
public:
TreeWalker(Accessible* aContext, nsIContent* aNode, bool aWalkCache = false);
virtual ~TreeWalker();
/**
* Return the next child accessible.
*
* @note Returned accessible is bound to the document, if the accessible is
* rejected during tree creation then the caller should be unbind it
* from the document.
*/
Accessible* NextChild()
{
return NextChildInternal(false);
}
private:
TreeWalker();
TreeWalker(const TreeWalker&);
TreeWalker& operator =(const TreeWalker&);
/**
* Return the next child accessible.
*
* @param aNoWalkUp [in] specifies the walk direction, true means we
* shouldn't go up through the tree if we failed find
* accessible children.
*/
Accessible* NextChildInternal(bool aNoWalkUp);
/**
* Create new state for the given node and push it on top of stack.
*
* @note State stack is used to navigate up/down the DOM subtree during
* accessible children search.
*/
bool PushState(nsIContent *aNode);
/**
* Pop state from stack.
*/
void PopState();
DocAccessible* mDoc;
Accessible* mContext;
int32_t mChildFilter;
bool mWalkCache;
WalkState* mState;
};
} // namespace a11y
} // namespace mozilla
#endif // mozilla_a11y_TreeWalker_h_