Note
Please see Azure Cognitive Services for Speech documentation for the latest supported speech solutions.
Microsoft Speech Platform
ISpNotifySource::SetNotifyCallbackFunction
ISpNotifySource::SetNotifyCallbackFunction sets up this instance to send notifications using a standard C-style callback function.
<pre IsFakePre="true" xmlns="http://www.w3.org/1999/xhtml"> <strong>HRESULT SetNotifyCallbackFunction(</strong> <strong>SPNOTIFYCALLBACK</strong> <em>*pfnCallback</em>, <strong>WPARAM</strong> <em>wParam</em>, <strong>LPARAM</strong> <em>lParam</em> <strong>);</strong> </pre>
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 | Description |
|---|---|
| S_OK | Function completed successfully. |
| E_INVALIDARG | Callback function is invalid. |
| FAILED (hr) | Appropriate error message. |
Remarks
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 Speech Platform 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);