IViewObject::SetAdvise 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       aspects,
  DWORD       advf,
  IAdviseSink *pAdvSink
);

Parameters

aspects

View for which the advisory connection is being set up. Valid values are taken from the enumeration DVASPECT. See the DVASPECT enumeration for more information.

advf

Contains a group of flags for controlling the advisory connection. Valid values are from the enumeration ADVF. However, only some of the possible ADVF values are relevant for this method. The following table briefly describes the relevant values. See the ADVF enumeration for a more detailed description.

Value Meaning
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.
 
Note  The ADVF_ONLYONCE and ADVF_PRIMEFIRST can be combined to provide an asynchronous call to IDataObject::GetData.
 

pAdvSink

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 returns S_OK on success. Other possible return values include the following.

Return code Description
OLE_E_ADVISENOTSUPPORTED
Advisory notifications are not supported.
DV_E_DVASPECT
Invalid value for dwAspect.
E_INVALIDARG
One or more of the supplied values is invalid.
E_OUTOFMEMORY
Insufficient memory available for this operation.

Remarks

A container application that is requesting a draw operation on a view object can also register with the IViewObject::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 IViewObject::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 IViewObject::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.

Requirements

   
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header oleidl.h

See Also

ADVF

IAdviseSink

IViewObject

IViewObject::GetAdvise