gecko/accessible/src/base/AccIterator.h

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 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
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 *
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 * for the specific language governing rights and limitations under the
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 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is
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 * Contributor(s):
 *  Alexander Surkov <surkov.alexander@gmail.com> (original author)
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#ifndef nsAccIterator_h_
#define nsAccIterator_h_

#include "filters.h"
#include "nscore.h"

/**
 * Allows to iterate through accessible children or subtree complying with
 * filter function.
 */
class AccIterator
{
public:
  /**
   * Used to define iteration type.
   */
  enum IterationType {
    /**
     * Navigation happens through direct children.
     */
    eFlatNav,

    /**
     * Navigation through subtree excluding iterator root; if the accessible
     * complies with filter, iterator ignores its children.
     */
    eTreeNav
  };

  AccIterator(nsAccessible* aRoot, filters::FilterFuncPtr aFilterFunc,
              IterationType aIterationType = eFlatNav);
  ~AccIterator();

  /**
   * Return next accessible complying with filter function. Return the first
   * accessible for the first time.
   */
  nsAccessible *GetNext();

private:
  AccIterator();
  AccIterator(const AccIterator&);
  AccIterator& operator =(const AccIterator&);

  struct IteratorState
  {
    IteratorState(nsAccessible *aParent, IteratorState *mParentState = nsnull);

    nsAccessible *mParent;
    PRInt32 mIndex;
    IteratorState *mParentState;
  };

  filters::FilterFuncPtr mFilterFunc;
  PRBool mIsDeep;
  IteratorState *mState;
};

#endif