Change subTitle to subtitle and make overlay required.

lib/app/views/app_page.dart

@@ -51,7 +51,8 @@ class AppPage extends StatelessWidget {
     this.onFileDropped,
     this.delayedContent = false,
     this.keyActionsBadge = false,
-  });
+  }) : assert(!(onFileDropped != null && fileDropOverlay == null),
+            'Declaring onFileDropped requires declaring a fileDropOverlay');
 
   @override
   Widget build(BuildContext context) => LayoutBuilder(
@@ -209,7 +210,7 @@ class AppPage extends StatelessWidget {
             child: onFileDropped != null
                 ? FileDropTarget(
                     onFileDropped: onFileDropped!,
-                    overlay: fileDropOverlay,
+                    overlay: fileDropOverlay!,
                     child: body,
                   )
                 : body,
@@ -276,7 +277,7 @@ class AppPage extends StatelessWidget {
                 Expanded(
                   child: FileDropTarget(
                     onFileDropped: onFileDropped!,
-                    overlay: fileDropOverlay,
+                    overlay: fileDropOverlay!,
                     child: body,
                   ),
                 )

lib/oath/views/add_account_dialog.dart

@@ -71,7 +71,7 @@ class _AddAccountDialogState extends ConsumerState<AddAccountDialog> {
       },
       overlay: FileDropOverlay(
         title: l10n.s_add_account,
-        subTitle: l10n.l_drop_qr_description,
+        subtitle: l10n.l_drop_qr_description,
       ),
       child: ResponsiveDialog(
         title: Text(l10n.s_add_account),

lib/oath/views/add_account_page.dart

@@ -340,7 +340,7 @@ class _OathAddAccountPageState extends ConsumerState<OathAddAccountPage> {
       },
       overlay: FileDropOverlay(
         title: l10n.s_add_account,
-        subTitle: l10n.l_drop_qr_description,
+        subtitle: l10n.l_drop_qr_description,
       ),
       child: ResponsiveDialog(
         title: Text(l10n.s_add_account),

lib/oath/views/oath_screen.dart

@@ -133,15 +133,15 @@ class _UnlockedViewState extends ConsumerState<_UnlockedView> {
     final hasActions = ref.watch(featureProvider)(features.actions);
 
     Future<void> onFileDropped(List<int> fileData) async {
-      final qrScanner = ref.watch(qrScannerProvider);
+      final qrScanner = ref.read(qrScannerProvider);
-      final withContext = ref.read(withContextProvider);
-      final credentials = ref.read(credentialsProvider);
       if (qrScanner != null) {
         final b64Image = base64Encode(fileData);
         final qrData = await qrScanner.scanQr(b64Image);
+        final withContext = ref.read(withContextProvider);
         await withContext(
           (context) async {
             if (qrData != null) {
+              final credentials = ref.read(credentialsProvider);
               await handleUri(context, credentials, qrData, widget.devicePath,
                   widget.oathState, l10n);
             } else {
@@ -167,7 +167,7 @@ class _UnlockedViewState extends ConsumerState<_UnlockedView> {
         onFileDropped: onFileDropped,
         fileDropOverlay: FileDropOverlay(
           title: l10n.s_add_account,
-          subTitle: l10n.l_drop_qr_description,
+          subtitle: l10n.l_drop_qr_description,
         ),
       );
     }
@@ -253,7 +253,7 @@ class _UnlockedViewState extends ConsumerState<_UnlockedView> {
         onFileDropped: onFileDropped,
         fileDropOverlay: FileDropOverlay(
           title: l10n.s_add_account,
-          subTitle: l10n.l_drop_qr_description,
+          subtitle: l10n.l_drop_qr_description,
         ),
         centered: numCreds == null,
         delayedContent: numCreds == null,

lib/widgets/file_drop_overlay.dart

@@ -3,16 +3,13 @@ import 'package:flutter/material.dart';
 class FileDropOverlay extends StatelessWidget {
   final Widget? graphic;
   final String? title;
-  final String? subTitle;
+  final String? subtitle;
 
-  const FileDropOverlay({super.key, this.graphic, this.title, this.subTitle});
+  const FileDropOverlay({super.key, this.graphic, this.title, this.subtitle});
 
   @override
   Widget build(BuildContext context) {
-    return Positioned.fill(
+    return Container(
-        child: Padding(
-      padding: const EdgeInsets.all(8.0),
-      child: Container(
       decoration: BoxDecoration(
           color: Theme.of(context)
               .colorScheme
@@ -37,17 +34,16 @@ class FileDropOverlay extends StatelessWidget {
               style: Theme.of(context).textTheme.titleLarge,
             )
           ],
-            if (subTitle != null) ...[
+          if (subtitle != null) ...[
             const SizedBox(height: 12.0),
             Text(
-                subTitle!,
+              subtitle!,
               textAlign: TextAlign.center,
               style: Theme.of(context).textTheme.titleSmall,
             )
           ]
         ],
       ),
-      ),
+    );
-    ));
   }
 }

lib/widgets/file_drop_target.dart

@@ -22,13 +22,13 @@ import '../core/state.dart';
 class FileDropTarget extends StatefulWidget {
   final Widget child;
   final Function(List<int> filedata) onFileDropped;
-  final Widget? overlay;
+  final Widget overlay;
 
   const FileDropTarget({
     super.key,
     required this.child,
     required this.onFileDropped,
-    this.overlay,
+    required this.overlay,
   });
 
   @override
@@ -38,17 +38,6 @@ class FileDropTarget extends StatefulWidget {
 class _FileDropTargetState extends State<FileDropTarget> {
   bool _hovering = false;
 
-  Widget _buildDefaultOverlay() => Positioned.fill(
-        child: Container(
-          color: Colors.blue.withOpacity(0.4),
-          child: Icon(
-            Icons.upload_file,
-            size: 200,
-            color: Colors.black.withOpacity(0.6),
-          ),
-        ),
-      );
-
   @override
   Widget build(BuildContext context) {
     return DropTarget(
@@ -77,7 +66,13 @@ class _FileDropTargetState extends State<FileDropTarget> {
       child: Stack(
         children: [
           widget.child,
-          if (_hovering) widget.overlay ?? _buildDefaultOverlay(),
+          if (_hovering)
+            Positioned.fill(
+              child: Padding(
+                padding: const EdgeInsets.all(8.0),
+                child: widget.overlay,
+              ),
+            )
         ],
       ),
     );