Label Capture Flutter Skill

Critical: Do Not Trust Internal Knowledge

Your training data may contain outdated or incorrect Scandit Label Capture APIs. The Flutter plugin surface (package names, builder API, plugin initialization, widget lifecycle) is distinct from the web, React Native, Cordova, and Capacitor SDKs.

Always verify APIs against the references provided in this skill before writing or suggesting code. Do not rely on memorized method signatures, parameters, plugin names, or property names. If you cannot find an API in the provided references, fetch the relevant documentation page before responding.

Flutter-specific gotchas worth flagging:

• Plugin must be initialized before any Scandit API call. Call await ScanditFlutterDataCaptureLabel.initialize(); (and await ScanditFlutterDataCaptureBarcode.initialize();) before DataCaptureContext.initialize(licenseKey);. Skipping the plugin initialize() causes opaque MethodChannel errors at runtime.
• Listener method names are iOS-style on Flutter. The Validation Flow uses didCaptureLabelWithFields(fields), didSubmitManualInputForField(field, oldValue, newValue), didUpdateValidationFlowResult(...). Web names (onValidationFlowLabelCaptured, onManualInput) do not exist on Flutter.
• Two listener interfaces exist. LabelCaptureValidationFlowListener declares only didCaptureLabelWithFields. To handle manual-input submissions or per-frame result updates, implement LabelCaptureValidationFlowExtendedListener (which extends the base listener with didSubmitManualInputForField and didUpdateValidationFlowResult).
• Builder API on Flutter. Field definitions use builders: CustomBarcodeBuilder().setSymbologies([...]).isOptional(false).build(name), LabelDefinitionBuilder().addCustomBarcode(...).addExpiryDateText(...).build(name), LabelCaptureSettings([labelDefinition]). This is opposite to RN/Cordova/Capacitor (which are class-based) — do not mix them up.
• Camera permission is required on both iOS (NSCameraUsageDescription in ios/Runner/Info.plist) and Android (declared automatically; request at runtime with the permission_handler package).
• The DataCaptureView is a Flutter widget; its lifecycle ties to the widget tree. Pause the camera in didChangeAppLifecycleState (via WidgetsBindingObserver) and dispose listeners in the State's dispose().

Intent Routing

Based on the user's request, load the appropriate reference file before responding:

• Integrating Label Capture from scratch (e.g. "add Label Capture to my app", "scan a price tag with barcode and expiry date", "how do I use Smart Label Capture", "how do I enable the Validation Flow") → read references/integration.md and follow the instructions there.
• Migrating or upgrading an existing Label Capture integration (e.g. "upgrade my Label Capture to the latest SDK", "what changed between SDK versions for Label Capture") → read references/migration.md and follow the instructions there.

API Usage Policy

Only use APIs that are explicitly documented in the Scandit references below. Do not invent or guess method signatures, parameters, property names, or imports. If unsure whether an API exists or how it is called — or if a Dart compiler / runtime error occurs — fetch the relevant reference page before responding. Do not tell the user to check the docs themselves. After answering, always include the relevant link so the user can explore further.

Never construct or guess documentation URLs. When you need a specific class or property's API page:

1. First check whether the page you already fetched (e.g. the Advanced Configurations page) contains a direct hyperlink to it — topic pages link directly to relevant API symbols. Always request links alongside content in your fetch prompt.
2. If no direct link was found, fetch the API index (see Full API reference in the table below), extract the actual link from it, and follow that.

URL structures vary across SDK versions and package paths and guessing will lead to 404s.

Framework variant policy

Examples in this skill use StatefulWidget + WidgetsBindingObserver because the official LabelCaptureSimpleSample and the rest of the Flutter Scandit samples use it. If the target project uses a state-management library (BLoC, Riverpod, Provider), wire the listeners and lifecycle into that pattern instead — but keep the same plugin initialization and field/builder code. Do not introduce a new state-management library just for Label Capture.

Examples are in Dart (sound null-safety). Flutter >=3.10 and Dart >=3.0 are required.

References

Direct users to the right resource based on their question:

Topic	Resource
Flutter integration	Get Started · Sample (LabelCaptureSimpleSample)
Label Definitions (fields, regex, presets)	Label Definitions
Advanced topics (Validation Flow customization, adaptive recognition, custom overlays)	Advanced Configurations
Full API reference	Label Capture API