IWMStatusCallback::OnStatus

The OnStatus method is called when status information must be communicated by the reader to the host application. This happens routinely when a Windows Media file is being opened and read, and when errors occur during reading.

Syntax

HRESULT OnStatus(
  WMT_STATUS  Status,
  HRESULT  hr,
  WMT_ATTR_DATATYPE  dwType,
  BYTE*  pValue,
  void*  pvContext
);

Parameters

Status

[in] Specifies one member of the WMT_STATUS enumeration type. For a description of possible WMT_STATUS members, see the table in the Remarks section.

[in] Specifies an HRESULT error code.

dwType

[in] Double word containing a value of WMT_ATTR_DATATYPE type, indicating what this OnStatus call means.

pValue

[in] Pointer to a value object.

pvContext

[in] Universal pointer to the context. This context pointer matches the context passed to IWMReader::Open, IWMReader::Start, or IWMIndexer::StartIndexing.

Return Values

If the method succeeds, it returns S_OK. If it fails, it returns an HRESULT error code.

Remarks

The contents of pParam depend on those of Status.

The WMT_STATUS members that can be returned by the IWMReaderCallback method are as follows.

Members	Number	Description
WMT_ERROR	0	An error occurred in reading the file.
WMT_OPENED	1	The file has been opened for reading.
WMT_BUFFERING_START	2	The reader has started buffering data.
WMT_BUFFERING_STOP	3	The reader has stopped buffering data.
WMT_EOF	4	The reader has reached the end of the file.
WMT_END_OF_FILE	4	The reader has reached the end of the file.
WMT_END_OF_SEGMENT	5	When the Start() method is called with a duration argument, WMT_END_OF_SEGMENT is returned when playback has been completed after the specified period. The argument is a QWORD indicating duration of playback in 100-nanosecond units.
WMT_END_OF_STREAMING	6	The file has finished streaming.
WMT_LOCATING	7	Locating a server.
WMT_CONNECTING	8	Connecting to a server.
WMT_NO_RIGHTS	9	The reader does not have the appropriate rights to access this file.
WMT_MISSING_CODEC	10	The reader does not have the appropriate codec to decompress this file.
WMT_STARTED	11	The reader has started reading the file
WMT_STOPPED	12	The reader has stopped reading the file.
WMT_CLOSED	13	The reader has closed the file.
WMT_STRIDING	14	The reader is seeking through the file.
WMT_TIMER	15	A timer event has occurred.

The WMT_STATUS enumerated types that can be returned by the IWMIndexer::StartIndexing method are as follows.

Members	Number	Description
WMT_ERROR	0	An error occurred in reading the file.
WMT_OPENED	1	The file has been opened for indexing.
WMT_STARTED	11	The indexer has started indexing the file
WMT_STOPPED	12	The indexer has stopped indexing the file.
WMT_CLOSED	13	The indexer has closed the file.
WMT_INDEX_PROGRESS	16	Indicates the progress of the current indexing operation. The argument is a double word that indicates percentage completed, ranging from 0 to 100.

See Also

IWMReaderCallback Interface

Previous

Next