ISpNotifySource::SetNotifyCallbackFunction (SAPI 5.4)
Microsoft Speech API 5.4
ISpNotifySource::SetNotifyCallbackFunction sets up this instance to send notifications using a standard C-style callback function.
HRESULT SetNotifyCallbackFunction( SPNOTIFYCALLBACK *pfnCallback, WPARAM wParam, LPARAM lParam );
[in] The notification callback function to be used.
[in] Constant WPARAM value that will be passed to the pfnCallback function when it is called.
[in] Constant LPARAM value that will be passed to the pfnCallback function when it is called.
It is the responsibility of the client code to control the lifetime of a notification. To remove an installed notify callback, call ISpEventSource::SetNotifySink (NULL). The final release of an object that supports ISpEventSource will automatically remove an installed notify callback.
The SAPI implementation uses a hidden window to call back the client on the same thread that was used to initialize the event source. Notification callbacks are the result of processing a window message. When this notification mechanism is used:
- The SPNOTIFYCALLBACK method will always be called on the thread that initialized the event source or notify translator object.
- The thread must have a window message pump.
The SPNOTIFYCALLBACK function is declared as follows:
typedef void __stdcall SPNOTIFYCALLBACK(WPARAM wParam, LPARAM lParam);