/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * 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
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Communicator client code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Original Author: David W. Hyatt (hyatt@netscape.com)
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
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 * decision by deleting the provisions above and replace them with the notice
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 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#ifndef nsIScrollbarListener_h___
#define nsIScrollbarListener_h___

// {A0ADBD81-2911-11d3-97FA-00400553EEF0}
#define NS_ISCROLLBARLISTENER_IID \
{ 0xa0adbd81, 0x2911, 0x11d3, { 0x97, 0xfa, 0x0, 0x40, 0x5, 0x53, 0xee, 0xf0 } }

static NS_DEFINE_IID(kIScrollbarListenerIID,     NS_ISCROLLBARLISTENER_IID);

class nsPresContext;

class nsIScrollbarListener : public nsISupports {

public:

  NS_DECLARE_STATIC_IID_ACCESSOR(NS_ISCROLLBARLISTENER_IID)
  
  NS_IMETHOD PositionChanged(nsPresContext* aPresContext, PRInt32 aOldIndex, PRInt32& aNewIndex) = 0;

  NS_IMETHOD PagedUpDown() = 0;
};

NS_DEFINE_STATIC_IID_ACCESSOR(nsIScrollbarListener, NS_ISCROLLBARLISTENER_IID)

#endif