Document capture

Capture of identity documents. The SDK presents a frame to assist the user in positioning the document; after positioning, the user clicks the button to capture the photo.

No content validation

The SDK does not perform any type of validation on what is being captured.

Available document frames

Frame	Description
`DocumentCameraTypes.CPF`	Capture the CPF
`DocumentCameraTypes.CNH`	Capture the open CNH
`DocumentCameraTypes.CNH_FRENTE`	Capture the front of the CNH
`DocumentCameraTypes.CNH_VERSO`	Capture the back of the CNH
`DocumentCameraTypes.RG_FRENTE`	Capture the front of the RG
`DocumentCameraTypes.RG_VERSO`	Capture the back of the RG
`DocumentCameraTypes.OUTROS("descrição")`	Generic frame for any other document

Generic frame

If you need to capture a document for which there is no specific frame (e.g., RNE), use DocumentCameraTypes.OUTROS("description") — a generic, rectangular frame that can be used to guide any capture.

For the full list of supported document types, see API Reference > Enums.

Starting a document capture

Step 1 — Implement UnicoListener

UnicoListener handles the SDK lifecycle callbacks. Implement the four mandatory methods:

Method	When it's called
`onErrorUnico(error)`	An error occurred during SDK operation
`onUserClosedCameraManually()`	The user manually closed the camera
`onSystemClosedCameraTimeoutSession()`	The 40-second session limit was reached
`onSystemChangedTypeCameraTimeoutFaceInference()`	No face detected for 13 seconds — switches to manual capture

class _MyHomePageState extends State<MyHomePage> implements UnicoListener {
  late UnicoCheckBuilder _unicoCheck;

  @override
  void onErrorUnico(UnicoError error) {}

  @override
  void onUserClosedCameraManually() {}

  @override
  void onSystemClosedCameraTimeoutSession() {}

  @override
  void onSystemChangedTypeCameraTimeoutFaceInference() {}
}

Mandatory listener methods

All four listener methods above must be created in your project (even without any logic). Otherwise, the project will not compile successfully.

Step 2 — Implement the document listeners

Add the document callbacks to your state class:

Method	Description
`onSuccessDocument(ResultCamera resultCamera)`	Capture succeeded — returns `ResultCamera` with `base64` (preview) and `encrypted` (JWT for the API)
`onErrorDocument(UnicoError error)`	Capture failed — returns a `UnicoError` with code and description

@override
void onSuccessDocument(ResultCamera resultCamera) { }

@override
void onErrorDocument(UnicoError error) { }

Step 3 — Call openCameraDocument

The openCameraDocument() method is provided through the object generated with an instance of the UnicoCheck class. It takes:

A JSON file with the credentials, generated in the credential setup step;
The document type to be captured (DocumentType enum);
The listener configured in Step 2.

Example using the open CNH:

_unicoCheck.build().openCameraDocument(
  jsonFileName: androidJsonFileName,
  documentType: DocumentType.CNH,
  listener: this,
);

For the full result handling, see Receiving the result.