gecko-dev/view/public/nsIScrollPositionListener.h

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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
// {98a0c040-09cf-408b-b55f-321b4f8d9d67}

#define NS_ISCROLLPOSITIONLISTENER_IID \
    { 0x98a0c040, 0x09cf, 0x408b, \
      { 0xb5, 0x5f, 0x32, 0x1b, 0x4f, 0x8d, 0x9d, 0x67 } }

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

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

NS_DEFINE_STATIC_IID_ACCESSOR(nsIScrollPositionListener,
                              NS_ISCROLLPOSITIONLISTENER_IID)

#endif /* nsIScrollPositionListener_h___ */