ISpNotifyTranslator::InitCallback (SAPI 5.3)

Microsoft Speech API 5.3

ISpNotifyTranslator::InitCallback

ISpNotifyTranslator::InitCallback sets up this instance to send notifications using a standard C-style callback function.

  
    HRESULT InitCallback(
   SPNOTIFYCALLBACK   *pfnCallback,
   WPARAM              wParam,
   LPARAM              lParam
);

Parameters

• pfnCallback
  [in] The notification callback function to be used.
• wParam
  [in] Constant WPARAM value that will be passed to the pfnCallback function when it is called.
• lParam
  [in] Constant LPARAM value that will be passed to the pfnCallback function when it is called.

Return values

Value

S_OK

SPERR_ALREADY_INITIALIZED

E_INVALIDARG

FAILED(hr)

Remarks

The translator implementation uses a hidden window to call back the client on the same thread that was used to initialize the event source. Notify callbacks are the result of processing a window message. When this notification mechanism is used:

1. The SPNOTIFYCALLBACK method will always be called on the thread that initialized the event source or notify translator object.
2. The thread must have a window message pump.

The SPNOTIFYCALLBACK function is declared as follows:

    typedef void __stdcall SPNOTIFYCALLBACK(WPARAM wParam, LPARAM lParam);