[This is preliminary documentation and subject to change.]
The ITVControl interface is a sink that enables objects to receive notifications of changes in the state of WebTV for Windows.
Implement ITVControl if you are developing a television-aware control that resides in the WebTV for Windows container, or if your control needs notification of WebTV for Windows events.
Note Currently, WebTV for Windows only sends notifications to applications running in the same process as WebTV for Windows. An example of such an application is a Microsoft® ActiveX® control or component called from an enhancement page that is currently being displayed by WebTV for Windows.
WebTV for Windows calls the methods of ITVControl to notify registered objects of a change in the WebTV for Windows state.
IUnknown Methods | Description |
QueryInterface | Returns pointers to supported interfaces |
AddRef | Increments reference count |
Release | Decrements reference count |
ITVControl | Description |
---|---|
OnIdle | Advises that idle-time processing is available. |
Tune | Advises that WebTV for Windows has tuned to a new channel. |
TearDown | Advises that WebTV for Windows is closing the current World Wide Web page. |
SyncEvent | Advises that a sync event has occurred. |
EpisodeStatusChanged | Advises that the status of an episode has changed. |
PowerChange | Advises that the system power is turning on or turning off. |
OnTVFocus | Advises that WebTV for Windows has gotten focus. |
SetOutput | Advises that the control should set an additional output device, for example a VCR. |
GetCC | Returns the closed-captioning status of the control. |
SetCC | Advises that the closed-captioning status has changed in WebTV for Windows. |
EnableVideo | Advises that the control that the status of the video display has changed. |
After your object has registered a sink, it should advise on the ITVControl connection point when it is user interface–activated, able to interact with the user, and revoke the connection point when it is user interface–deactivated, or hidden. In other words, the control should advise when it receives a IOleObject::DoVerb method call specifying the value OLEVERB_UIACTIVATE, OLEVERB_INPLACEACTIVATE, or OLEVERB_PRIMARY, and the control should revoke the connection point when it receives a IOleObject::DoVerb call specifying the value OLEVERB_HIDE.
To locate more information about the IOleObject interface and the DoVerb method, see Further Information on Television Services for the Client.
ITelevisionServices is derived from the IDispatch interface. To locate more information on IDispatch, a Component Object Model (COM) interface, see Further Information on Television Services for the Client.
Windows NT: Unsupported.
Windows: Requires Windows 98.
Windows CE: Unsupported.
Header: Declared in tvdisp.odl.
Import Library: User-defined.
Unicode: Yes.