| elementName | [ElementName](js-apis-bundleManager-elementName.md#elementname) | Yes| Application description, which consists of the bundle name and component name.|
| elementName | [ElementName](js-apis-bundleManager-elementName.md#elementname) | Yes| Application description, which consists of the bundle name and component name.|
| type | [CardType](#cardtype9) | Yes| Card emulation service type.|
| type | [CardType](#cardtype9) | Yes | Card emulation service type. |
| type | string | Yes| Event type to unsubscribe from. The value is **nfcStateChange**.|
| type | string | Yes| Event type to unsubscribe from. The value is **nfcStateChange**.|
| callback | Callback<[NfcState](#nfcstate)> | No| Callback for the NFC state changes. This parameter can be left blank.|
| callback | Callback<[NfcState](#nfcstate)> | No| Callback for the NFC state changes. This parameter can be left blank. If this parameter is not specified, all callbacks associated with the specified event will be unregistered.|