1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/accessible/src/base/TreeWalker.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,95 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#ifndef mozilla_a11y_TreeWalker_h_
1.10 +#define mozilla_a11y_TreeWalker_h_
1.11 +
1.12 +#include "mozilla/Attributes.h"
1.13 +#include <stdint.h>
1.14 +
1.15 +class nsIContent;
1.16 +
1.17 +namespace mozilla {
1.18 +namespace a11y {
1.19 +
1.20 +class Accessible;
1.21 +class DocAccessible;
1.22 +
1.23 +struct WalkState;
1.24 +
1.25 +/**
1.26 + * This class is used to walk the DOM tree to create accessible tree.
1.27 + */
1.28 +class TreeWalker MOZ_FINAL
1.29 +{
1.30 +public:
1.31 + enum {
1.32 + // used to walk the existing tree of the given node
1.33 + eWalkCache = 1,
1.34 + // used to walk the context tree starting from given node
1.35 + eWalkContextTree = 2 | eWalkCache
1.36 + };
1.37 +
1.38 + /**
1.39 + * Constructor
1.40 + *
1.41 + * @param aContext [in] container accessible for the given node, used to
1.42 + * define accessible context
1.43 + * @param aNode [in] the node the search will be prepared relative to
1.44 + * @param aFlags [in] flags (see enum above)
1.45 + */
1.46 + TreeWalker(Accessible* aContext, nsIContent* aNode, uint32_t aFlags = 0);
1.47 + ~TreeWalker();
1.48 +
1.49 + /**
1.50 + * Return the next child accessible.
1.51 + *
1.52 + * @note Returned accessible is bound to the document, if the accessible is
1.53 + * rejected during tree creation then the caller should be unbind it
1.54 + * from the document.
1.55 + */
1.56 + Accessible* NextChild()
1.57 + {
1.58 + return NextChildInternal(false);
1.59 + }
1.60 +
1.61 +private:
1.62 + TreeWalker();
1.63 + TreeWalker(const TreeWalker&);
1.64 + TreeWalker& operator =(const TreeWalker&);
1.65 +
1.66 + /**
1.67 + * Return the next child accessible.
1.68 + *
1.69 + * @param aNoWalkUp [in] specifies the walk direction, true means we
1.70 + * shouldn't go up through the tree if we failed find
1.71 + * accessible children.
1.72 + */
1.73 + Accessible* NextChildInternal(bool aNoWalkUp);
1.74 +
1.75 + /**
1.76 + * Create new state for the given node and push it on top of stack.
1.77 + *
1.78 + * @note State stack is used to navigate up/down the DOM subtree during
1.79 + * accessible children search.
1.80 + */
1.81 + void PushState(nsIContent* aNode);
1.82 +
1.83 + /**
1.84 + * Pop state from stack.
1.85 + */
1.86 + void PopState();
1.87 +
1.88 + DocAccessible* mDoc;
1.89 + Accessible* mContext;
1.90 + int32_t mChildFilter;
1.91 + uint32_t mFlags;
1.92 + WalkState* mState;
1.93 +};
1.94 +
1.95 +} // namespace a11y
1.96 +} // namespace mozilla
1.97 +
1.98 +#endif // mozilla_a11y_TreeWalker_h_
