Camera Scanner Kit

A production-grade, highly optimized Flutter UI toolkit for barcode and QR scanning that solves camera lifecycle bugs and turns raw streams into fully-wired retail and warehouse workflows.

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Why Camera Scanner Kit?

While packages like mobile_scanner provide the raw camera stream, integrating them into a real-world app is notoriously error-prone. Developers constantly fight with native camera-lock hangs, "ghost scans" during exit animations, deactivated-widget context crashes, and lack of visual overlays.

camera_scanner_kit wraps the raw scanner in an enterprise-ready shell featuring:

• 9-in-1 Routing Matrix: Instantly launch single-scan, batch-accumulate, or streaming modes with customized barcode, QR, or manual overlays.
• Hardware-Safe Tripwires: Failsafe hooks that guarantee the camera sensor is fully detached and released before screen transitions begin, ending "deactivated widget" crashes forever.
• Built-in POS Mode: A complete Point of Sale scanning interface featuring live quantity increment/decrement controls, ghost success pulses, and a reactive checkout cart summary.
• Low-Latency Native Feedback: Direct integration with native haptic and audio APIs for ultra-low latency scan confirmation beeps.
• Collapsible Inline View: An embeddable BarcodeScannerView that slides open/shut like a window blind and automatically sleeps during periods of inactivity.

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Installation

Add camera_scanner_kit to your pubspec.yaml:

dependencies:
  camera_scanner_kit: ^1.0.2

Platform Setup

Android

Add the camera permission to your AndroidManifest.xml (usually under android/app/src/main/AndroidManifest.xml):

<uses-permission android:name="android.permission.CAMERA" />

iOS

Add the camera usage description to your Info.plist (usually under ios/Runner/Info.plist):

<key>NSCameraUsageDescription</key>
<string>This app requires camera access to scan barcodes.</string>

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Getting Started

1. Single Scan Mode

Open the camera, scan exactly one item, and automatically pop the screen to return the value.

import 'package:camera_scanner_kit/camera_scanner_kit.dart';

void startSingleScan(BuildContext context) async {
  // scanBarcode is optimized with a wide horizontal 1D cutout
  final String? barcode = await scanBarcode(context);
  
  if (barcode != null) {
    print('Scanned barcode: $barcode');
  }
}

2. POS Mode (With Quantity Controls)

Launch a full retail checkout scanner with quantity adjustment controls (+/-) and a live cart preview sheet.

import 'package:camera_scanner_kit/camera_scanner_kit.dart';

void openCheckout(BuildContext context) {
  showPosBarcodeScanner(
    context,
    onScan: (barcode, quantity) {
      print('Adding $quantity of $barcode to checkout cart');
    },
  );
}

3. Inline Mode (Embeddable Widget)

Embed a scanning window directly inside your existing UI (e.g. form fields or lists). Includes a smooth expand/collapse transition.

import 'package:camera_scanner_kit/camera_scanner_kit.dart';

class MyInlineForm extends StatelessWidget {
  final BarcodeScannerController _controller = BarcodeScannerController();

  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        BarcodeScannerView(
          controller: _controller,
          onBarcodeScanned: (barcode) {
            print('Inline scan: $barcode');
          },
        ),
        ElevatedButton(
          onPressed: () => _controller.toggle(),
          child: ListenableBuilder(
            listenable: _controller,
            builder: (context, _) {
              return Text(_controller.isCameraActive ? 'Close Scanner' : 'Open Scanner');
            },
          ),
        ),
      ],
    );
  }
}

💡 Programmatic Control (v1.0.2+): In addition to toggle(), you can call _controller.start() and _controller.stop() for explicit, idempotent control. Both are safe to call repeatedly — calling start() on an already-active camera (or stop() on an already-stopped one) is a no-op.

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API Reference

Facade Functions (functions.dart)

Function	Mode	Overlay Shape	Return Type
scanBarcode()	Single	1D Horizontal	Future<String?>
scanQrCode()	Single	1:1 Square	Future<String?>
scanCustom()	Single	Custom Rect	Future<String?>
scanBarcodeBatch()	Batch	1D Horizontal	Future<List<String>?>
scanQrCodeBatch()	Batch	1:1 Square	Future<List<String>?>
scanCustomBatch()	Batch	Custom Rect	Future<List<String>?>
scanBarcodeStream()	Stream	1D Horizontal	Future<void> (fires onCameraScan)
scanQrCodeStream()	Stream	1:1 Square	Future<void> (fires onCameraScan)
scanCustomStream()	Stream	Custom Rect	Future<void> (fires onCameraScan)

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License

This package is licensed under the MIT License - see the LICENSE file for details.