Working, but bad recognition in landscape.

@@ -12,8 +12,6 @@ import 'package:mobile_scanner_example/mobile_scanner_overlay.dart';
 import 'package:mobile_scanner_example/picklist/picklist_result.dart';
 
 void main() async {
-  WidgetsFlutterBinding.ensureInitialized();
-  await SystemChrome.setPreferredOrientations([DeviceOrientation.portraitUp]);
   runApp(
     const MaterialApp(
       title: 'Mobile Scanner Example',

 import 'dart:async';
 
 import 'package:flutter/material.dart';
-import 'package:flutter/services.dart';
 import 'package:mobile_scanner/mobile_scanner.dart';
-import 'package:mobile_scanner_example/picklist/classes/detect_collision.dart';
+import 'package:mobile_scanner_example/picklist/classes/barcode_at_center.dart';
+
 import 'package:mobile_scanner_example/picklist/widgets/crosshair.dart';
 import 'package:mobile_scanner_example/scanner_error_widget.dart';
 
@@ -21,13 +21,12 @@ class _BarcodeScannerPicklistState extends State<BarcodeScannerPicklist>
   );
   StreamSubscription<Object?>? _barcodesSubscription;
 
-  final _scannerDisabled = ValueNotifier(false);
+  final _scannerEnabled = ValueNotifier(true);
 
   bool barcodeDetected = false;
 
   @override
   void initState() {
-    SystemChrome.setPreferredOrientations([DeviceOrientation.portraitUp]);
     WidgetsBinding.instance.addObserver(this);
     _barcodesSubscription = _mobileScannerController.barcodes.listen(
       _handleBarcodes,
@@ -69,17 +68,14 @@ class _BarcodeScannerPicklistState extends State<BarcodeScannerPicklist>
   }
 
   void _handleBarcodes(BarcodeCapture capture) {
-    if (_scannerDisabled.value) {
+    if (!_scannerEnabled.value) {
       return;
     }
 
     for (final barcode in capture.barcodes) {
-      if (isPointInPolygon(
-        Offset(
-          _mobileScannerController.value.size.width / 2,
-          _mobileScannerController.value.size.height / 2,
-        ),
-        barcode.corners,
+      if (isBarcodeAtCenterOfImage(
+        cameraOutputSize: _mobileScannerController.value.size,
+        barcode: barcode,
       )) {
         if (!barcodeDetected) {
           barcodeDetected = true;
@@ -92,14 +88,7 @@ class _BarcodeScannerPicklistState extends State<BarcodeScannerPicklist>
 
   @override
   Widget build(BuildContext context) {
-    const boxFit = BoxFit.contain;
-    return PopScope(
-      onPopInvokedWithResult: (didPop, result) {
-        if (didPop) {
-          SystemChrome.setPreferredOrientations([...DeviceOrientation.values]);
-        }
-      },
-      child: Scaffold(
+    return Scaffold(
       appBar: AppBar(title: const Text('Picklist scanner')),
       backgroundColor: Colors.black,
       body: StreamBuilder(
@@ -107,9 +96,9 @@ class _BarcodeScannerPicklistState extends State<BarcodeScannerPicklist>
         builder: (context, snapshot) {
           return Listener(
             behavior: HitTestBehavior.opaque,
-              onPointerDown: (_) => _scannerDisabled.value = true,
-              onPointerUp: (_) => _scannerDisabled.value = false,
-              onPointerCancel: (_) => _scannerDisabled.value = false,
+            onPointerDown: (_) => _scannerEnabled.value = false,
+            onPointerUp: (_) => _scannerEnabled.value = true,
+            onPointerCancel: (_) => _scannerEnabled.value = true,
             child: Stack(
               fit: StackFit.expand,
               children: [
@@ -117,13 +106,13 @@ class _BarcodeScannerPicklistState extends State<BarcodeScannerPicklist>
                   controller: _mobileScannerController,
                   errorBuilder: (context, error, child) =>
                       ScannerErrorWidget(error: error),
-                    fit: boxFit,
+                  fit: BoxFit.contain,
                 ),
                 ValueListenableBuilder(
-                    valueListenable: _scannerDisabled,
+                  valueListenable: _scannerEnabled,
                   builder: (context, value, child) {
                     return Crosshair(
-                        scannerDisabled: value,
+                      scannerEnabled: value,
                     );
                   },
                 ),
@@ -132,7 +121,6 @@ class _BarcodeScannerPicklistState extends State<BarcodeScannerPicklist>
           );
         },
       ),
-      ),
     );
   }
 }

 import 'package:flutter/material.dart';
+import 'package:mobile_scanner/mobile_scanner.dart';
 
-bool isPointInPolygon(Offset point, List<Offset> polygon) {
+bool isBarcodeAtCenterOfImage({
+  required Size cameraOutputSize,
+  required Barcode barcode,
+}) {
+  final centerOfCameraOutput = Offset(
+    cameraOutputSize.width / 2,
+    cameraOutputSize.height / 2,
+  );
+  debugPrint(cameraOutputSize.toString());
+  return _isPointInPolygon(
+    point: centerOfCameraOutput,
+    polygon: barcode.corners,
+  );
+}
+
+//This is what chatGPT came up with.
+//https://en.wikipedia.org/wiki/Point_in_polygon
+bool _isPointInPolygon({
+  required Offset point,
+  required List<Offset> polygon,
+}) {
   int i;
   int j = polygon.length - 1;
   bool inside = false;

@@ -3,17 +3,17 @@ import 'package:flutter/material.dart';
 class Crosshair extends StatelessWidget {
   const Crosshair({
     super.key,
-    required this.scannerDisabled,
+    required this.scannerEnabled,
   });
 
-  final bool scannerDisabled;
+  final bool scannerEnabled;
 
   @override
   Widget build(BuildContext context) {
     return Center(
       child: Icon(
         Icons.close,
-        color: scannerDisabled ? Colors.green : Colors.red,
+        color: scannerEnabled ? Colors.red : Colors.green,
       ),
     );
   }