Select a Terminal

The following code snippet demonstrates selecting terminals onto streams associated with a call.

Before using this code snippet, you must perform the operations in Initialize TAPI and Select an Address.

Also, this snippet requires that the application already have a pointer to the ITBasicCallControl interface of either an incoming or outgoing call. See Make a Call or Receive a Call for code snippets on how to obtain this pointer.

Note  This snippet does not have the error checking and releases appropriate for real code.

C++ Code Snippet[C++]

// pAddress is an ITAddress interface pointer.
// pBasicCall is an ITBasicCallControl interface pointer.

// Get the ITStreamControl interface.
ITStreamControl * pStreamControl;
pBasicCall->QueryInterface(
    IID_ITStreamControl,
    (void **) &pStreamControl
    );

// Enumerate the streams and select 
// terminals onto them.
IEnumStream * pEnumStreams;
ITStream    * pStream;
pStreamControl->EnumerateStreams(&pEnumStreams);
while ( S_OK == pEnumStreams->Next(1, &pStream, NULL) )
    {
        // Get the media type and direction of this stream.
        long                lMediaType;
        TERMINAL_DIRECTION  dir;
        pStream->get_MediaType( &lMediaType );
        pStream->get_Direction( &dir );

        // Create the default terminal for this media type
        // and direction.
        //   If lMediaType == TAPIMEDIATYPE_VIDEO and
        //   dir == TD_RENDER, a dynamic video render terminal
        //   is required. Please see Incoming.cpp in 
        //   the samples section of the SDK. 
        // For all other terminals, get the default 
        // static terminal.
        ITTerminal * pTerminal;
        ITTerminalSupport * pTerminalSupport;
        pAddress->QueryInterface( 
            IID_ITTerminalSupport, 
            (void **)&pTerminalSupport
            );
        pTerminalSupport->GetDefaultStaticTerminal(
            lMediaType,
            dir,
            pTerminal
            );
        // Select the terminal on the stream.
        pStream->SelectTerminal(pTerminal);
    }

Visual Basic Code Snippet[Visual Basic]

'query for ITBasicCallControl, the call control interface
Dim objCallControl As ITBasicCallControl
Set objCallControl = gobjReceivedCallInfo

'query ITTerminalSupport from Address object
Dim objTerminalSupport As ITTerminalSupport
Set objTerminalSupport = gobjAddress

Dim objTerminal As ITTerminal
Set objTerminal = objTerminalSupport.GetDefaultStaticTerminal _
    lMediaType, dir)

'release not needed objects
Set objTerminalSupport = Nothing

'Select the terminal before answering
'we'll need the ITStreamControl interface for doing this.

Dim objStreamControl As ITStreamControl
Set objStreamControl = objCallControl

If Not (objStreamControl Is Nothing) Then
    Dim objITCollStreams As ITCollection
    
    Set objITCollStreams = objStreamControl.Streams
    
    Dim nIndex As Long, objCrtStream As ITStream
    
    For nIndex = 1 To objITCollStreams.Count
        Set objCrtStream = objITCollStreams.Item(nIndex)
        If objCrtStream.MediaType = lMediaType  Then
            If objCrtStream.Direction = dir Then
                Call objCrtStream.SelectTerminal(objTerminal)
            End If
        End If
        Set objCrtStream = Nothing
    Next nIndex
    
    Set objITCollStreams = Nothing
    Set objStreamControl = Nothing
End If

See Also

ITAddress, ITBasicCallControl, ITStreamControl, ITStream, IEnumStream, ITTerminal, ITTerminalSupport