add scanfield

lib/widgets/scanner.dart

@@ -59,12 +59,24 @@ class MyScanner extends StatelessWidget {
 
     return settingsProvider.scanning
         ? Expanded(
-            child: MobileScanner(
+            child: Stack(
+            alignment: Alignment.center,
+            children: [
+              MobileScanner(
                 fit: BoxFit.contain,
                 controller: MobileScannerController(
                   detectionTimeoutMs: 2000,
                 ),
-                onDetect: onDetect))
+                onDetect: onDetect,
+              ),
+              ClipRRect(
+                  borderRadius: BorderRadius.circular(20),
+                  child: Container(
+                      height: MediaQuery.of(context).size.height / 3,
+                      width: MediaQuery.of(context).size.width * 0.8,
+                      color: Colors.white.withOpacity(0.4))),
+            ],
+          ))
         : RoundButton(
             onPressed: () => settingsProvider.scanning = true,
             iconData: Icons.qr_code_scanner_outlined,