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4/8/2010

This pure virtual class enables control points to receive notifications, and devices to send notifications, about state variable changes.

Syntax 

class IEventSink

Methods

The following table shows the method in this class.

Method Description

IEventSink::OnStateChanged

Called when a state variable maintained by a service changes.

Remarks

To receive notifications, control points create an instance of an object that inherits from this class and pass a pointer to this object to the IEventSource::Advisemethod exposed by the service from which they want to receive notifications.

Devices notify control points of state variables changes by calling OnStateChanged.

The implementation of these methods provided by the UPnP AV Framework uses UPnP event subscriptions and UPnP event notifications to connect control points and devices. From the perspective of code in the control point and device implementation, the device calls OnStateChangedand the corresponding OnStateChangedmethod is called in the control point's IEventSinkimplementation. The UPnP AV Framework implements this connection using proxy classes that in turn use UPnP eventing.

All of the UPnP AV Framework service classes - IAVTransport, IConnectionManager, IContentDirectory, and IRenderingControl- implement IEventSourceand therefore accept IEventSinkreferences to which they provide state variable notifications.

Requirements

Header av_upnp.h
Library Av_upnp.lib
Windows Embedded CE Windows CE 5.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also