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Register Events

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The following code examples demonstrate implementation of a simple event handler, registration of the main TAPI event interface, setting of the event filter, and registration for call notifications.

The event handler shown is an example rather than a requirement. The primary goal is to ensure that the thread that receives events does minimal processing before passing work to another thread. This prevents the event handler from becoming a performance problem in situations of high event load.

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

Note

This example does not have the error checking and releases appropriate for production code.

 

//
// Example 1: Implement a simple event handler.
//
HRESULT STDMETHODCALLTYPE
CTAPIEventNotification::Event(
    TAPI_EVENT  TapiEvent,
    IDispatch * pEvent
    )
{
    // AddRef the event so it does not go away.
    pEvent->AddRef();

    // Post a message to our own UI thread.
    BOOL bMessage;
    bMessage = PostMessage( 
                           ghDlg,
                           WM_PRIVATETAPIEVENT,
                           (WPARAM) TapiEvent,
                           (LPARAM) pEvent
                           );
    // If (bMessage == 0) process the error here. 
    return S_OK;
}

//
// Example 2: Register the event interface.
//
long                         gulAdvise;  // Globally declared
IConnectionPointContainer   * pCPC;
IConnectionPoint            * pCP;
IUnknown                    * pUnk;

// Get the connection point container interface pointer from the TAPI object.
hr = gpTapi->QueryInterface(
      IID_IConnectionPointContainer,
      (void **)&pCPC
);
// If ( hr != S_OK O) process the error here. 

// Get the ITTAPIEventNotification interface pointer from the container.
hr = pCPC->FindConnectionPoint(
      IID_ITTAPIEventNotification,
      &pCP
     );
// If ( hr != S_OK O) process the error here. 

pCPC->Release();

// Create a private event notification object.
CTAPIEventNotification* pTapiEventNotification = new CTAPIEventNotification;

hr = pTapiEventNotification->QueryInterface(
      IID_IUnknown,
      (void **)&pUnk
     );
// If ( hr != S_OK O) process the error here. 

// Call the advise method to give TAPI the IUnknown pointer for the event handler.
hr = pCP->Advise(
      pUnk,
      (ULONG *)&gulAdvise
     );
// If ( hr != S_OK O) process the error here. 

pCP->Release();

//
// Example 3: Set the event filter.
//
// Assume we are interested only in call-related events.
hr = gpTapi->put_EventFilter(
    TE_CALLNOTIFICATION | TE_CALLSTATE | TE_CALLMEDIA
    );
// If ( hr != S_OK O) process the error here. 

//
// Example 4: Register an address with TAPI
// for call notifications. Assume we are interested
// in video and audio calls, and that pAddress
// is a pointer to the ITAddress interface of
// an address that can handle both media types.

long glRegister; // Globally declared

hr = gpTapi->RegisterCallNotifications(
      pAddress,
      VARIANT_TRUE,   // monitor privileges
      VARIANT_TRUE,   // owner privileges
      TAPIMEDIATYPE_AUDIO|TAPIMEDIATYPE_VIDEO,
      gulAdvise,      // As returned by Advise
      &glRegister
      );
// If ( hr != S_OK O) process the error here.

ITTAPIEventNotification::Event

TAPI_EVENT

ITTAPI::put_EventFilter

TAPIMEDIATYPE_ Constants

ITTAPI::RegisterCallNotifications