ScannerController class

Standalone controller managing hardware camera lifecycle, frame throttling, adaptive frame processing, background isolate execution, ROI cropping, performance metrics telemetry, scan history, auto-zoom, and low-light controls.

Inheritance

Object
ChangeNotifier
ScannerController

Mixed-in types

WidgetsBindingObserver

Constructors

ScannerController({ScanMode initialMode = ScanMode.qr, ResolutionPreset resolutionPreset = cam.ResolutionPreset.high, ScannerOptions options = const ScannerOptions(), dynamic onResultDetected(ScanResult result)?, dynamic onLowLightDetected(bool isLowLight)?, dynamic onStatsUpdated(ScannerStats stats)?, dynamic onFrame(CameraImage frame)?, UniversalScanEngine? scanEngine, ImagePicker? imagePicker}): Constructs a ScannerController.

Properties

activeSession → MultiScanSession?: Currently active multi-scan session (null if no session active).
no setter
analytics → ScannerAnalytics: Enterprise session telemetry analytics tracker.
final
autoCaptureMachine → AutoCaptureStateMachine: final
autoZoomController → AutoZoomController: final
availableCameras → List<CameraDescription>: List of available hardware cameras on device.
no setter
barcodeTracker → BarcodeDecoderEngine: final
batchResults → List<ScanResult>: List of accumulated scan results collected in ScanStrategy.batch mode.
no setter
cameraController → CameraController?: Active camera controller instance, if initialized.
no setter
currentLuminosity → double: Ambient frame relative brightness score (0.0 to 1.0).
no setter
currentMode → ScanMode: Alias for active scanning mode.
no setter
currentZoomLevel → double: Current digital zoom level setting (1.0 to maxZoomLevel).
no setter
documentSession → DocumentScanSession?: no setter
errorMessage → String?: Last error message encountered during camera or scan operations.
no setter
facing → CameraFacing: Hardware camera lens facing direction (mobile_scanner API compatibility).
no setter
fpsState → ScannerFpsState: no setter
hashCode → int: The hash code for this object.
no setterinherited
hasListeners → bool: Whether any listeners are currently registered.
no setterinherited
historyController ↔ ScanHistoryController: Dedicated scan history controller for recording, searching, and exporting scan results.
latefinal
isBlurry → bool: Whether last evaluated frame was blurry.
no setter
isDisposed → bool: Whether controller has been disposed.
no setter
isFlashOn → bool: Whether flash/torch is currently turned on.
no setter
isFocusLocked → bool: Whether autofocus is currently locked.
no setter
isInitialized → bool: Whether camera controller and ML engine are initialized and ready.
no setter
isInitializing → bool: Whether camera initialization is currently in progress.
no setter
isLowLight → bool: Whether camera scene is currently under low ambient lighting.
no setter
isMotionDetected → bool: Whether significant camera shaking or motion was detected.
no setter
isPaused → bool: Whether live stream processing is currently paused.
no setter
lastResult → ScanResult?: Most recently detected ScanResult.
no setter
lastTapFocusPoint → Offset?: Most recent tap-to-focus point coordinates.
no setter
maxZoomLevel → double: no setter
minZoomLevel → double: no setter
motionScore → double: Motion magnitude score.
no setter
onFrame → dynamic Function(CameraImage frame)?: Optional callback invoked on each raw live camera image frame for custom ML AI models.
final
onFrameStream → Stream<CameraImage>: Stream emitting raw live camera image frames for custom ML AI pipelines.
no setter
onLowLightDetected → dynamic Function(bool isLowLight)?: Optional callback invoked when ambient light changes (low light alert).
final
onLowLightStateChanged → Stream<bool>: Stream emitting low light status alerts.
no setter
onResult → Stream<ScanResult>: Stream emitting valid detected ScanResult objects.
no setter
onResultDetected → dynamic Function(ScanResult result)?: Optional callback invoked when a valid scan result is detected.
final
onStats → Stream<ScannerStats>: Stream emitting real-time performance telemetry.
no setter
onStatsUpdated → dynamic Function(ScannerStats stats)?: Optional callback invoked when internal performance telemetry updates.
final
options → ScannerOptions: Configuration options controlling scan strategy, ROI, throttling, and timeouts.
final
resolutionPreset → ResolutionPreset: Active resolution preset setting.
no setter
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
scanHistory → List<ScanResult>: In-memory log of recent scan history.
no setter
selectedCameraIndex → int: Currently selected camera index in availableCameras.
no setter
selectedMode → ScanMode: Currently active scanning mode.
no setter
stats → ScannerStats: Current internal telemetry snapshot.
no setter
torchLevel → double: Torch intensity brightness setting.
no setter
torchState → TorchState: Flashlight torch operation mode (mobile_scanner API compatibility).
no setter

Methods

addListener(VoidCallback listener) → void: Register a closure to be called when the object changes.
inherited
analyzeImage(String imagePath, {ScanMode? mode}) → Future<ScanResult>: Analyzes an image file from local path (mobile_scanner API compatibility).
autoZoomTo(double targetZoom) → Future<void>: Auto-zooms by multiplier when small barcodes are far away.
availableCamerasFunc() → Future<List<CameraDescription>>: Exposed for testing dependency injection.
clearBatch() → void: Clears accumulated batch inventory scan list.
clearHistory() → void: Clears in-memory scan history log.
didChangeAccessibilityFeatures() → void: Called when the system changes the set of currently active accessibility features.
inherited
didChangeAppLifecycleState(AppLifecycleState state) → void: Called when the system puts the app in the background or returns the app to the foreground.
override
didChangeLocales(List<Locale>? locales) → void: Called when the system tells the app that the user's locale has changed. For example, if the user changes the system language settings.
inherited
didChangeMetrics() → void: Called when the application's dimensions change. For example, when a phone is rotated.
inherited
didChangePlatformBrightness() → void: Called when the platform brightness changes.
inherited
didChangeTextScaleFactor() → void: Called when the platform's text scale factor changes.
inherited
didChangeViewFocus(ViewFocusEvent event) → void: Called whenever the PlatformDispatcher receives a notification that the focus state on a view has changed.
inherited
didHaveMemoryPressure() → void: Called when the system is running low on memory.
inherited
didPopRoute() → Future<bool>: Called when the system tells the app to pop the current route, such as after a system back button press or back gesture.
inherited
didPushRoute(String route) → Future<bool>: Called when the host tells the application to push a new route onto the navigator.
inherited
didPushRouteInformation(RouteInformation routeInformation) → Future<bool>: Called when the host tells the application to push a new RouteInformation and a restoration state onto the router.
inherited
didRequestAppExit() → Future<AppExitResponse>: Called when a request is received from the system to exit the application.
inherited
dispose() → void: Discards any resources used by the object.
override
endSession() → SessionStats?: Ends the active multi-scan session.
exportBatchCsv() → String: Exports accumulated batch results to CSV string format.
exportBatchJson() → String: Exports accumulated batch results to JSON string format.
handleCancelBackGesture() → void: Called when a predictive back gesture is canceled, indicating that no navigation should occur.
inherited
handleCommitBackGesture() → void: Called when a predictive back gesture is finished successfully, indicating that the current route should be popped.
inherited
handleStartBackGesture(PredictiveBackEvent backEvent) → bool: Called at the start of a predictive back gesture.
inherited
handleStatusBarTap() → void: Called when the user taps the status bar on iOS, to scroll a scroll view to the top.
inherited
handleUpdateBackGestureProgress(PredictiveBackEvent backEvent) → void: Called when a predictive back gesture moves.
inherited
initialize() → Future<void>: Initializes hardware cameras and starts live stream processing with auto-recovery.
inputImageFromBytes(Uint8List bytes, int width, int height, int bytesPerRow) → InputImage?
lockFocus() → Future<void>: Locks autofocus to current focal plane to prevent continuous hunting.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
notifyListeners() → void: Call all the registered listeners.
inherited
pauseScanning() → void: Pauses processing live stream image frames.
pickAndScanImage({ScanMode? mode}) → Future<ScanResult?>: Opens gallery image picker and scans selected image file.
pinchZoom(double scale) → Future<void>: Performs pinch zoom calculations based on gesture scale factor.
processBytes(Uint8List bytes, {ScanMode? mode, int width = 640, int height = 480}) → Future<ScanResult>: Processes raw byte buffer directly from memory.
processImageFile(String imagePath, {ScanMode? mode}) → Future<ScanResult>: Processes an image file from a local path.
removeBatchItem(int index) → void: Removes an item from batch scan list by index.
removeListener(VoidCallback listener) → void: Remove a previously registered closure from the list of closures that are notified when the object changes.
inherited
resumeScanning() → void: Resumes processing live stream image frames.
scanAll({ScanMode? mode}) → Future<List<ScanResult>>: Executes a multi-code batch pass returning all detected ScanResult items in a single scan.
scanAsset(String assetPath, {ScanMode? mode}) → Future<ScanResult>: Scans an image loaded from a Flutter asset path.
scanBytes(Uint8List bytes, {ScanMode? mode, int? width, int? height}) → Future<ScanResult>: Scans raw byte buffer directly from memory.
scanGallery({ScanMode? mode}) → Future<ScanResult?>: Alias for pickAndScanImage for gallery scanning.
scanImage(File imageFile, {ScanMode? mode}) → Future<ScanResult>: Scans a local image file directly from a File object.
setAutofocus(bool enabled) → Future<void>: Toggles continuous autofocus mode.
setCameraFacing(CameraFacing targetFacing) → Future<void>: Switches camera lens facing direction (mobile_scanner API compatibility).
setExposureCompensation(double offset) → Future<void>: Sets camera exposure compensation offset.
setExposureOffset(double offset) → Future<void>: Sets exposure compensation offset value.
setFlashMode(FlashMode mode) → Future<void>: Sets explicit flash mode.
setFocusPoint(Offset point) → Future<void>: Sets manual focus point on camera viewport coordinates (0.0 to 1.0).
setMode(ScanMode mode) → void: Sets active scan mode.
setResolution(ResolutionPreset preset) → Future<void>: Dynamically changes hardware camera resolution preset.
setTorchBrightness(double level) → Future<void>: Sets flashlight torch brightness level.
setTorchLevel(double level) → Future<void>: Sets torch level brightness intensity (0.0 to 1.0).
setTorchState(TorchState state) → Future<void>: Switches flashlight torch operation state (mobile_scanner API compatibility).
setZoomLevel(double zoom) → Future<void>: Sets absolute camera digital zoom level.
setZoomScale(double zoom) → Future<void>: Sets camera digital zoom scale (mobile_scanner API compatibility).
start() → Future<void>: Starts or resumes scanner operation (mobile_scanner API compatibility).
startDocumentSession({String? name, int? maxPages}) → DocumentScanSession: Starts a new multi-page document scanning session (scanbot_sdk style).
startSession({String? name, int? maxItems}) → MultiScanSession: Starts a new multi-scan session.
stop() → Future<void>: Stops or pauses scanner operation (mobile_scanner API compatibility).
switchCamera() → Future<void>: Switches to next available camera.
tapToFocus(Offset relativePoint) → Future<void>: Trigger tap-to-focus on camera preview coordinates.
toggleFlash() → Future<void>: Toggles camera flash (torch mode / off).
toString() → String: A string representation of this object.
inherited
unlockFocus() → Future<void>: Unlocks focus to resume continuous autofocus.
warmup() → Future<void>: Pre-warms vision engine and hardware resources prior to UI layout assembly.

Operators

operator ==(Object other) → bool: The equality operator.
inherited

Static Methods

prewarm() → Future<void>: Global static helper to pre-warm ML Kit engines and camera hardware before UI build.