IMMNotificationClient::OnDeviceStateChanged method (mmdeviceapi.h)

Article
02/22/2024

The OnDeviceStateChanged method indicates that the state of an audio endpoint device has changed.

Syntax

HRESULT OnDeviceStateChanged(
  [in] LPCWSTR pwstrDeviceId,
  [in] DWORD   dwNewState
);

Parameters

[in] pwstrDeviceId

Pointer to the endpoint ID string that identifies the audio endpoint device. This parameter points to a null-terminated, wide-character string containing the endpoint ID. The string remains valid for the duration of the call.

[in] dwNewState

Specifies the new state of the endpoint device. The value of this parameter is one of the following DEVICE_STATE_XXX constants:

DEVICE_STATE_ACTIVE

DEVICE_STATE_DISABLED

DEVICE_STATE_NOTPRESENT

DEVICE_STATE_UNPLUGGED

Return value

If the method succeeds, it returns S_OK. If it fails, it returns an error code.

Remarks

For a code example that implements the OnDeviceStateChanged method, see Device Events.

Requirements

Requirement	Value
Minimum supported client	Windows Vista [desktop apps only]
Minimum supported server	Windows Server 2008 [desktop apps only]
Target Platform	Windows
Header	mmdeviceapi.h