---
title: Callback / Listener interfaces
canonical: https://developer.unico.io/developers/sdks-and-tools/ios/api-reference/callback-listener-interfaces
locale: en
generated_by: markdown-export
---

- [/](/)
- [SDKs and Tools](/developers/sdks-and-tools/overview)
- [iOS SDK](/developers/sdks-and-tools/ios/requirements)
- API Reference
- Callback / Listener interfaces

# Callback / Listener interfaces

AcessoBioManagerDelegate (lifecycle)
| Method | Trigger |
| --- | --- |
| `onErrorAcessoBioManager(_ error: ErrorBio!)` | Implementation error during SDK operation |
| `onUserClosedCameraManually()` | User closed the camera manually |
| `onSystemClosedCameraTimeoutSession()` | Session expired due to timeout (default: 40 s) |
| `onSystemChangedTypeCameraTimeoutFaceInference()` | No face detected for 13 s — capture switches to manual |

AcessoBioSelfieDelegate (selfie)
| Method | Trigger |
| --- | --- |
| `onSuccessSelfie(_ result: SelfieResult!)` | Selfie capture succeeded |
| `onSuccess(_ result: SuccessResult!)` | User Journey completed — returns the `processId`. Required in a Unico API integration |
| `onErrorSelfie(_ errorBio: ErrorBio!)` | Selfie capture failed |

AcessoBioDocumentDelegate (document)
| Method | Trigger |
| --- | --- |
| `onSuccessDocument(_ result: DocumentResult!)` | Document capture succeeded |
| `onErrorDocument(_ errorBio: ErrorBio!)` | Document capture failed |

SelfieCameraDelegate / DocumentCameraDelegate (preparation)
| Method | Trigger |
| --- | --- |
| `onCameraReady(_ cameraOpener: AcessoBioCameraOpenerDelegate!)` | Selfie camera is ready to be opened |
| `onCameraFailed(_ message: ErrorPrepare!)` | Selfie camera preparation failed |
| `onCameraReadyDocument(_ cameraOpener: AcessoBioCameraOpenerDelegate!)` | Document camera is ready to be opened |
| `onCameraFailedDocument(_ message: ErrorPrepare!)` | Document camera preparation failed |

`ErrorPrepare`The `ErrorPrepare` type is an extension of `ErrorBio`, thus containing all of its properties.

Last updated on **Oct 23, 2026**