IEventSink (Windows Embedded CE 6.0)
1/6/2010
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 |
|---|---|
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::Advise method 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 OnStateChanged and the corresponding OnStateChanged method is called in the control point's IEventSink implementation. 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 IEventSource and therefore accept IEventSink references 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 |
See Also
Reference
UPnP AV Interface and Implementation Classes
IAVTransport
IConnectionManager
IContentDirectory
IEventSource
IEventSource::Advise
IRenderingControl