Collecting the Responses

The startOcr method returns a Future<OcrReturnValues>. No manual JSON decoding is needed — the plugin already delivers typed Dart objects.

OcrReturnValues

class OcrReturnValues {
  final List<DocumentRecognitionItem> documentRecognitionResponse;
}

Attribute	Type	Description
documentRecognitionResponse	List<DocumentRecognitionItem>	List with one entry per capture performed by the user.

DocumentRecognitionItem

class DocumentRecognitionItem {
  final String? ocrKey;
  final String? ocrFrontKey;
  final String? ocrBackKey;
  final String documentType;
}

Attribute	Type	Description
ocrKey	String?	Image identification key, present for single-capture documents (cnhFull, cnhDigital, address, rgCinDigital). It can be used in any other service of the QI Tech system.
ocrFrontKey	String?	Identification key of the front image, present for dual-capture documents (cnh, rg, rne, crnm).
ocrBackKey	String?	Identification key of the back image, present for dual-capture documents (cnh, rg, rne, crnm).
documentType	String	Identifies which document that key refers to (e.g. "cnh", "rg", "proof_of_address").

Important

Store the returned keys — they are the image identifier in the other products of the QI Tech system, such as the Onboarding API.

Reading the response

final result = await plugin.startOcr(
  CaaSEnvironment.sandbox,
  '<YOUR_MOBILE_TOKEN_SENT_BY_QITECH>',
  CaaSDocumentType.cnh,
);

for (final item in result.documentRecognitionResponse) {
  if (item.ocrKey != null) {
    print('Ocr key: ${item.ocrKey} document type: ${item.documentType}');
  }
  if (item.ocrFrontKey != null) {
    print('Ocr front key: ${item.ocrFrontKey} document type: ${item.documentType}');
  }
  if (item.ocrBackKey != null) {
    print('Ocr back key: ${item.ocrBackKey} document type: ${item.documentType}');
  }
}

Error handling

Warning

Unlike startFaceRecon, which throws a typed FaceReconException, the startOcr method throws a String containing the error message. Use a generic catch (e).

try {
  final result = await plugin.startOcr(
    CaaSEnvironment.sandbox,
    '<YOUR_MOBILE_TOKEN_SENT_BY_QITECH>',
    CaaSDocumentType.cnh,
  );
  // ...
} catch (e) {
  print('Error executing OCR: $e');
}

Most common error messages

Message	Meaning
User canceled OCR	The user interrupted the capture flow before completing it.
Error executing OCR: <detail>	The native iOS SDK ended the flow with an error.
at startOcr: <detail>	A required parameter was missing from the call.
Activity is null	On Android, the SDK could not obtain the host activity.