fixed Boxfit.cover scanwindow alignment

@@ -166,7 +166,7 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
             result.success(answer)
         } else {
             val facing: Int = call.argument<Int>("facing") ?: 0
-            val ratio: Int? = call.argument<Int>("ratio")
+            val ratio: Int = call.argument<Int>("ratio") ?: 1
             val torch: Boolean = call.argument<Boolean>("torch") ?: false
             val formats: List<Int>? = call.argument<List<Int>>("formats")
 
@@ -197,6 +197,7 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
                     result.error("textureEntry", "textureEntry is null", null)
                     return@addListener
                 }
+                
                 // Preview
                 val surfaceProvider = Preview.SurfaceProvider { request ->
                     val texture = textureEntry!!.surfaceTexture()
@@ -207,17 +208,15 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
 
                 // Build the preview to be shown on the Flutter texture
                 val previewBuilder = Preview.Builder()
-                if (ratio != null) {
-                    previewBuilder.setTargetAspectRatio(ratio)
-                }
+                        .setTargetAspectRatio(ratio)
+                
                 preview = previewBuilder.build().apply { setSurfaceProvider(surfaceProvider) }
 
                 // Build the analyzer to be passed on to MLKit
                 val analysisBuilder = ImageAnalysis.Builder()
                         .setBackpressureStrategy(ImageAnalysis.STRATEGY_KEEP_ONLY_LATEST)
-                        .setTargetResolution(preview!!.resolutionInfo?.resolution ?: Size(640, 480))
+                        .setTargetAspectRatio(ratio) 
 
-                if (ratio != null) { analysisBuilder.setTargetAspectRatio(ratio) }
                 val analysis = analysisBuilder.build().apply { setAnalyzer(executor, analyzer) }
 
                 // Select the correct camera
@@ -228,7 +227,6 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
                 val analysisSize = analysis.resolutionInfo?.resolution ?: Size(0, 0)
                 val previewSize = preview!!.resolutionInfo?.resolution ?: Size(0, 0)
                 
-                
                 Log.i("LOG", "Analyzer: $analysisSize")
                 Log.i("LOG", "Preview: $previewSize")
 

@@ -22,10 +22,16 @@ class _BarcodeScannerWithScanWindowState
   }
 
   Future<void> restart() async {
-    await controller.stop();
+    // await controller.stop();
     await controller.start();
   }
 
+  Future<void> onDetect(Barcode barcode, MobileScannerArguments? _) async {
+    setState(() => this.barcode = barcode.rawValue);
+    await Future.delayed(const Duration(seconds: 1));
+    setState(() => this.barcode = '');
+  }
+
   @override
   Widget build(BuildContext context) {
     final scanWindow = Rect.fromCenter(
@@ -41,12 +47,11 @@ class _BarcodeScannerWithScanWindowState
           return Stack(
             children: [
               MobileScanner(
-                fit: BoxFit.contain,
+                fit: BoxFit.cover,
                 scanWindow: scanWindow,
                 controller: controller,
-                onDetect: (barcode, _) => setState(() {
-                  this.barcode = barcode.rawValue;
-                }),
+                onDetect: onDetect,
+                allowDuplicates: true,
               ),
               CustomPaint(
                 painter: ScannerOverlay(scanWindow),

 import 'package:flutter/foundation.dart';
-import 'package:flutter/material.dart';
+import 'package:flutter/material.dart' hide applyBoxFit;
 import 'package:mobile_scanner/mobile_scanner.dart';
+import 'package:mobile_scanner/src/objects/barcode_utility.dart';
 
 enum Ratio { ratio_4_3, ratio_16_9 }
 
@@ -89,22 +90,17 @@ class _MobileScannerState extends State<MobileScanner>
     Size textureSize,
     Size widgetSize,
   ) {
-
     /// map the texture size to get its new size after fitted to screen
-    final fittedSizes = applyBoxFit(fit, textureSize, widgetSize);
-    final fittedTextureSize = fittedSizes.destination;
+    final fittedTextureSize = applyBoxFit(fit, textureSize, widgetSize);
 
     /// create a new rectangle that represents the texture on the screen
     final minX = widgetSize.width / 2 - fittedTextureSize.width / 2;
     final minY = widgetSize.height / 2 - fittedTextureSize.height / 2;
-    final width = fittedTextureSize.width;
-    final height = fittedTextureSize.height;
-    final textureWindow = Rect.fromLTWH(minX, minY, width, height);
+    final textureWindow = Offset(minX, minY) & fittedTextureSize;
 
     /// create a new scan window and with only the area of the rect intersecting the texture window
     final scanWindowInTexture = scanWindow.intersect(textureWindow);
 
-
     /// update the scanWindow left and top to be relative to the texture not the widget
     final newLeft = scanWindowInTexture.left - textureWindow.left;
     final newTop = scanWindowInTexture.top - textureWindow.top;
@@ -114,21 +110,12 @@ class _MobileScannerState extends State<MobileScanner>
     /// new scanWindow that is adapted to the boxfit and relative to the texture
     final windowInTexture = Rect.fromLTWH(newLeft, newTop, newWidth, newHeight);
 
-    print(windowInTexture);
-
     /// get the scanWindow as a percentage of the texture
     final percentageLeft = windowInTexture.left / fittedTextureSize.width;
     final percentageTop = windowInTexture.top / fittedTextureSize.height;
     final percentageRight = windowInTexture.right / fittedTextureSize.width;
     final percentagebottom = windowInTexture.bottom / fittedTextureSize.height;
 
-    print(Rect.fromLTRB(
-      percentageLeft,
-      percentageTop,
-      percentageRight,
-      percentagebottom,
-    ));
-
     /// this rectangle can be send to native code and used to cut out a rectangle of the scan image
     return Rect.fromLTRB(
       percentageLeft,

+import 'dart:math' as math;
+
 import 'package:flutter/material.dart';
 import 'package:mobile_scanner/mobile_scanner.dart';
 
@@ -147,3 +149,79 @@ WiFi? toWiFi(Map? data) {
     return null;
   }
 }
+
+Size applyBoxFit(BoxFit fit, Size input, Size output) {
+  if (input.height <= 0.0 ||
+      input.width <= 0.0 ||
+      output.height <= 0.0 ||
+      output.width <= 0.0) {
+    return Size.zero;
+  }
+
+  Size destination;
+
+  final inputAspectRatio = input.width / input.height;
+  final outputAspectRatio = output.width / output.height;
+
+  switch (fit) {
+    case BoxFit.fill:
+      destination = output;
+      break;
+    case BoxFit.contain:
+      if (outputAspectRatio > inputAspectRatio) {
+        destination = Size(
+          input.width * output.height / input.height,
+          output.height,
+        );
+      } else {
+        destination = Size(
+          output.width,
+          input.height * output.width / input.width,
+        );
+      }
+      break;
+
+    case BoxFit.cover:
+      if (outputAspectRatio > inputAspectRatio) {
+        destination = Size(
+          output.width,
+          input.height * (output.width / input.width),
+        );
+      } else {
+        destination = Size(
+          input.width * (output.height / input.height),
+          output.height,
+        );
+      }
+      break;
+    case BoxFit.fitWidth:
+      destination = Size(
+        output.width,
+        input.height * (output.width / input.width),
+      );
+      break;
+    case BoxFit.fitHeight:
+      destination = Size(
+        input.width * (output.height / input.height),
+        output.height,
+      );
+      break;
+    case BoxFit.none:
+      destination = Size(
+        math.min(input.width, output.width),
+        math.min(input.height, output.height),
+      );
+      break;
+    case BoxFit.scaleDown:
+      destination = input;
+      if (destination.height > output.height) {
+        destination = Size(output.height * inputAspectRatio, output.height);
+      }
+      if (destination.width > output.width) {
+        destination = Size(output.width, output.width / inputAspectRatio);
+      }
+      break;
+  }
+
+  return destination;
+}