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IViewObject::SetAdvise

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This method establishes a connection between the view object and an advise sink so that the advise sink can be notified about changes in the object's view.

HRESULT SetAdvise( 
  DWORD dwAspect, 
  DWORD advf, 
  IAdviseSink* pAdvSink
);

Parameters

  • dwAspect
    [in] Specifies the view for which the advisory connection is being set up. Valid values are taken from the enumeration DVASPECT.

  • advf
    [in] Contains a group of flags for controlling the advisory connection. Valid values are from the enumeration ADVF. However, only the following ADVF values are relevant for this method.

    Value Description
    ADVF_ONLYONCE Causes the advisory connection to be destroyed after the first notification is sent.
    ADVF_PRIMEFIRST Causes an initial notification to be sent regardless of whether data has changed from its current state.

    For more information about the following values, see the ADVF enumeration.

    Note that the ADVF_ONLYONCE and ADVF_PRIMEFIRST can be combined to provide an asynchronous call to IDataObject::GetData.

  • pAdvSink
    [out] Pointer to the IAdviseSink interface on the advisory sink that is to be informed of changes. A NULL value deletes any existing advisory connection.

Return Values

This method supports the standard return values E_INVALIDARG and E_OUTOFMEMORY, as well as the values described in the following table.

Value Description
S_OK The advisory connection was successfully established.
OLE_E_ADVISENOTSUPPORTED Advisory notifications are not supported.
DV_E_DVASPECT Invalid value for dwAspect.

Remarks

A container application that is requesting a draw operation on a view object can also register with the SetAdvise method to be notified when the presentation of the view object changes. To find out about when an object's underlying data changes, you must call IDataObject::DAdvise separately.

To remove an existing advisory connection, call the SetAdvise method with pAdvSink set to NULL.

If the view object changes, a call is made to the appropriate advise sink through its IAdviseSink::OnViewChange method.

At any time, a given view object can support only one advisory connection. Therefore, when SetAdvise is called and the view object is already holding on to an advise sink pointer, OLE releases the existing pointer before the new one is registered.

To determine whether the platform supports this interface, see Determining Supported COM APIs.

Requirements

OS Versions: Windows CE 2.0 and later.
Header: Oleidl.h, Oleidl.idl.
Link Library: Oleaut32.lib, Uuid.lib.

See Also

IViewObject | Determining Supported COM APIs | IAdviseSink | IAdviseSink::OnViewChange | IDataObject::DAdvise | IDataObject::GetData

Last updated on Wednesday, April 13, 2005

© 2005 Microsoft Corporation. All rights reserved.