Interface IAudioDeviceEvents

Namespace

AudioDeviceLib.CoreAudioApi

Assembly

AudioDeviceLib.dll

Receives change notifications for the set of audio endpoints. Implement this and register it with RegisterDeviceNotification(IAudioDeviceEvents).

public interface IAudioDeviceEvents

Remarks

THREADING: these callbacks are raised by Windows Core Audio on arbitrary, non-UI threads, and may arrive concurrently. Keep every method fast and non-blocking, do your own synchronization when touching shared state, and marshal to a UI thread yourself if you need to update UI. Exceptions thrown from a callback are converted to an HRESULT and returned to the audio engine; prefer handling errors inside the callback.

Do NOT register/unregister notifications or dispose the AudioController from inside a callback - that reenters Core Audio while it is dispatching. The payload is plain data (endpoint ID strings and enums), so there is no live COM object to misuse.

Methods

OnDefaultDeviceChanged(DataFlow, Role, string)

Called when the default endpoint changes for a given data flow and role.

void OnDefaultDeviceChanged(DataFlow flow, Role role, string defaultDeviceId)

Parameters

flow DataFlow

The data-flow direction whose default changed (Render or Capture).

role Role

The role whose default changed - for example Communications distinguishes a change to the default communications device from the console/multimedia default.

defaultDeviceId string

The endpoint ID of the new default device, or null when there is no longer a default for this flow/role (e.g. the last matching device was removed).

Remarks

Called on an arbitrary, non-UI thread.

OnDeviceAdded(string)

Called when a new endpoint is added.

void OnDeviceAdded(string deviceId)

Parameters

deviceId string

The endpoint ID of the added device.

Remarks

Called on an arbitrary, non-UI thread.

OnDeviceRemoved(string)

Called when an endpoint is removed.

void OnDeviceRemoved(string deviceId)

Parameters

deviceId string

The endpoint ID of the removed device.

Remarks

Called on an arbitrary, non-UI thread.

OnDeviceStateChanged(string, DeviceState)

Called when an endpoint's state changes (active, disabled, not present or unplugged).

void OnDeviceStateChanged(string deviceId, DeviceState newState)

Parameters

deviceId string

The endpoint ID of the device whose state changed.

newState DeviceState

The new device state reported by the system.

Remarks

Called on an arbitrary, non-UI thread.

OnPropertyValueChanged(string, PropertyKey)

Called when a property value of an endpoint changes.

void OnPropertyValueChanged(string deviceId, PropertyKey key)

Parameters

deviceId string

The endpoint ID of the device whose property changed.

key PropertyKey

The property that changed. Use Name for a friendly name of the property.

Remarks

Called on an arbitrary, non-UI thread.