IViewObject::SetAdvise

A version of this page is also available for

Windows Embedded CE 6.0 R3

4/8/2010

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.

Syntax

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.

  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 Value

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

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

See Also

Reference

IViewObject
IAdviseSink
IAdviseSink::OnViewChange
IDataObject::DAdvise
IDataObject::GetData

Concepts

Determining Supported COM APIs