minor improvements

example/lib/main.dart

@@ -90,7 +90,6 @@ class _DemoPageState extends State<DemoPage> {
                         ? Duration.zero
                         : const Duration(milliseconds: 500),
                     tryInverted: true,
-                    actionButtonsAlignment: Alignment.bottomLeft,
                   ),
                   if (showDebugInfo)
                     DebugInfoWidget(
@@ -166,6 +165,12 @@ class _DemoPageState extends State<DemoPage> {
     }
   }
 
+  _onMultiScanModeChanged(bool isMultiScan) {
+    setState(() {
+      this.isMultiScan = isMultiScan;
+    });
+  }
+
   _showMessage(BuildContext context, String message) {
     ScaffoldMessenger.of(context).hideCurrentSnackBar();
     ScaffoldMessenger.of(context).showSnackBar(
@@ -179,10 +184,4 @@ class _DemoPageState extends State<DemoPage> {
       failedScans = 0;
     });
   }
-
-  _onMultiScanModeChanged(bool isMultiScan) {
-    setState(() {
-      this.isMultiScan = isMultiScan;
-    });
-  }
 }

lib/src/ui/reader_widget.dart

@@ -20,12 +20,14 @@ class ReaderWidget extends StatefulWidget {
     this.onControllerCreated,
     this.onMultiScanModeChanged,
     this.isMultiScan = false,
+    this.multiScanModeAlignment = Alignment.bottomRight,
+    this.multiScanModePadding = const EdgeInsets.all(10),
     this.codeFormat = Format.any,
     this.tryHarder = false,
     this.tryInverted = false,
     this.showScannerOverlay = true,
     this.scannerOverlay,
-    this.actionButtonsAlignment = Alignment.topCenter,
+    this.actionButtonsAlignment = Alignment.bottomLeft,
     this.actionButtonsPadding = const EdgeInsets.all(10),
     this.showFlashlight = true,
     this.showToggleCamera = true,
@@ -55,11 +57,18 @@ class ReaderWidget extends StatefulWidget {
   final Function(CameraController?)? onControllerCreated;
 
   /// Called when the multi scan mode is changed
+  /// When set to null, the multi scan mode button will not be displayed
   final Function(bool)? onMultiScanModeChanged;
 
   /// Allow multiple scans
   final bool isMultiScan;
 
+  /// Alignment for multi scan mode button
+  final AlignmentGeometry multiScanModeAlignment;
+
+  /// Padding for multi scan mode button
+  final EdgeInsetsGeometry multiScanModePadding;
+
   /// Code format to scan
   final int codeFormat;
 
@@ -395,8 +404,11 @@ class _ReaderWidgetState extends State<ReaderWidget>
             ),
           ),
         ),
+        if (widget.onMultiScanModeChanged != null)
           ScanModeDropdown(
             isMultiScan: isMultiScan,
+            alignment: widget.multiScanModeAlignment,
+            padding: widget.multiScanModePadding,
             onChanged: (bool value) {
               setState(() {
                 isMultiScan = value;

lib/src/ui/scan_mode_dropdown.dart

@@ -5,17 +5,22 @@ class ScanModeDropdown extends StatelessWidget {
     super.key,
     this.isMultiScan = false,
     this.onChanged,
+    this.alignment = Alignment.bottomRight,
+    this.padding = const EdgeInsets.all(10),
   });
 
   final bool isMultiScan;
   final Function(bool value)? onChanged;
 
+  final AlignmentGeometry alignment;
+  final EdgeInsetsGeometry padding;
+
   @override
   Widget build(BuildContext context) {
     return Align(
-      alignment: Alignment.bottomRight,
+      alignment: alignment,
       child: Padding(
-        padding: const EdgeInsets.all(10),
+        padding: padding,
         child: Container(
           padding: const EdgeInsets.symmetric(horizontal: 10),
           decoration: BoxDecoration(