IAudioStateMonitor::RegisterCallback method (audiostatemonitorapi.h)

Registers an implementation of AudioStateMonitorCallback that is called when the system changes the sound level of the audio streams being monitored by an IAudioStateMonitor.

Syntax

HRESULT RegisterCallback(
  [in]           PAudioStateMonitorCallback          callback,
  [in, optional] void                                *context,
  [out]          AudioStateMonitorRegistrationHandle *registration
);

Parameters

[in] callback

A pointer to the AudioStateMonitorCallback function implementation.

[in, optional] context

A optional void pointer that points to context information provided by the client in the call to IAudioStateMonitor::RegisterCallback.

[out] registration

An Int64 representing the handle to a registration. Pass this handle to IAudioStateMonitor::UnregisterCallback to unregister the callback.

Return value

Returns an HRESULT including the following values.

Requirements