label-capture-flutter

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Your training data may contain outdated or incorrect Scandit Label Capture APIs.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().

Product Guidance

Apply these rules whenever the user is making a design decision, not just an API question. They reflect how Scandit recommends Label Capture be integrated.

• Default to the Validation Flow. New integrations should use LabelCaptureValidationFlowOverlay, not LabelCaptureBasicOverlay. Recommend the basic/advanced overlay path only when the customer explicitly needs a live AR overlay or a UI that the Validation Flow's fixed layout cannot produce. See references/validation-flow.md.
• Validation Flow must be rendered full-screen. Do not place it inside a card, half-sheet, modal slice, or partial-height widget — the layout assumes full-screen height for the field checklist, manual-entry sheet, and keyboard.
• Prefer pre-made labels first, then pre-made fields, then custom. Try in this order: (1) does a pre-made label definition cover the use case? — LabelDefinition.vinLabelDefinitionWithName(name), LabelDefinition.priceCaptureDefinitionWithName(name), LabelDefinition.sevenSegmentDisplayLabelDefinitionWithName(name). (2) Can the label be built from pre-made fields? — ExpiryDateText, PackingDateText, DateText, WeightText, UnitPriceText, TotalPriceText, SerialNumberBarcode, PartNumberBarcode, ImeiOneBarcode, ImeiTwoBarcode. (3) Only as a last resort, fall back to CustomText / CustomBarcode.
• Start from the sample app on greenfield integrations. If the user is starting from scratch, recommend cloning LabelCaptureSimpleSample (link in the References table) and adapting it.
• Hand off to the data-capture-sdk skill for non-Label-Capture questions. If the user asks about another Scandit product (Barcode Capture, SparkScan, MatrixScan, ID Capture, etc.) or about choosing between products, defer to the data-capture-sdk skill instead of guessing.

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") → read references/integration.md. By default, integrate the Validation Flow (the integration guide leads with it).
• Validation Flow questions ("how do I customize it", "what can we change", "why is it implemented this way", "how do I react to manual edits", "can I change the colors") → read references/validation-flow.md.
• Visual customization beyond the Validation Flow ("live AR overlay", "draw a tag next to each captured field", "get the camera frame during scanning") → read references/customization.md.
• Adaptive Recognition Engine / cloud fallback / receipt scanning ("how do I enable ARE", "use cloud recognition", "scan a receipt", "AdaptiveRecognitionMode", "is ARE available in production") → read references/adaptive-recognition.md.
• Migrating or upgrading an existing Label Capture integration → read references/migration.md.

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.

Licence key

Scanning needs a Scandit licence key. For this skill the licence product is native and the licence platforms are ios and android.

Work through these in order — never block the user on MCP:

1. The Scandit MCP server is connected — call ensure_scanner_setup with product native and platforms ios and android, app_identifier (the app's bundle or application id; for web, its production domain, never localhost) and env_var SCANDIT_LICENSE_KEY. Do not run the command it returns. Then call get_license_key with the key's id, from that result or from list_license_keys; if list_license_keys shows the key is not a trial, ask the user before fetching it. Show at most a masked preview in chat; never print a full key.

2. It is not connected — tell the user once that they can connect the remote Scandit MCP server, https://ssl.scandit.com/mcp, in their MCP client, then continue from step 1. Do not edit MCP client configuration yourself.

   Authentication is browser-based, so it is not supported headless or in CI. The server provisions trial keys only; it never creates, revokes, or modifies production licences.

3. The user declines, or has no MCP client — they generate a key themselves at https://ssl.scandit.com (no account yet: https://ssl.scandit.com/dashboard/sign-up?p=test) and paste it in.

Then put the key into the code: write it into the licence-key call in place of the placeholder — the key get_license_key returned, or the one the user pastes or gives you — still showing only a masked preview in chat. Do not search the project, its files or the environment for a key.

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