gecko-dev/view/public/nsIScrollPositionListener.h

/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
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 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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 * The Original Code is Mozilla Communicator.
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 * The Initial Developer of the Original Code is
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 *   Patrick Beard
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#ifndef nsIScrollPositionListener_h___
#define nsIScrollPositionListener_h___

#include "nsISupports.h"
#include "nsCoord.h"

// forward declarations
class nsIScrollableView;

// IID for the nsIScrollPositionListener interface
// {f8dfc500-6ad1-11d3-8360-a3f373ff79fc}
#define NS_ISCROLLPOSITIONLISTENER_IID \
{ 0xf8dfc500, 0x6ad1, 0x11d3, { 0x83, 0x60, 0xa3, 0xf3, 0x73, 0xff, 0x79, 0xfc } }

/**
 * Provides a way for a client of an nsIScrollableView to learn about scroll position
 * changes.
 */
class nsIScrollPositionListener : public nsISupports {
public:
	NS_DEFINE_STATIC_IID_ACCESSOR(NS_ISCROLLPOSITIONLISTENER_IID)

	NS_IMETHOD ScrollPositionWillChange(nsIScrollableView* aScrollable, nscoord aX, nscoord aY) = 0;
	NS_IMETHOD ScrollPositionDidChange(nsIScrollableView* aScrollable, nscoord aX, nscoord aY) = 0;
};

#endif /* nsIScrollPositionListener_h___ */