IWiaTransferCallback::TransferCallback method

Provides progress and other notifications during a transfer.

Syntax

HRESULT TransferCallback(
  [in] LONG              lFlags,
  [in] WiaTransferParams *pWiaTransferParams
);

Parameters

lFlags [in]

Type: LONG

Currently unused. Should be set to zero.

pWiaTransferParams [in]

Type: WiaTransferParams*

Specifies a pointer to a WiaTransferParams structure.

Return value

Type: HRESULT

If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

Remarks

When this method is implemented by an image processing filter, the Windows Image Acquisition (WIA) 2.0 minidriver calls it during image acquisition to send progress messages back to the application.

A filter's IWiaTransferCallback::TransferCallback must delegate to the application callback's IWiaTransferCallback::TransferCallback method. Usually, the filter stream filters the data passed to it and writes the filtered data directly to the application provided stream. When image processing filter stores data between calls to its IStream::Write method, it must also modify the lPercentComplete and ulBytesWrittenToCurrentStream values in the WiaTransferParams structure.

Requirements

Requirement	Value
Minimum supported client	Windows Vista [desktop apps only]
Minimum supported server	Windows Server 2008 [desktop apps only]
Header	Wia.h
IDL	Wia.idl
Library	Wiaguid.lib