组件优化

lib/views/public/scan_page.dart

@@ -10,6 +10,10 @@ class ScanPage extends StatefulWidget {
 class _ScanPageState extends State<ScanPage> {
   @override
   Widget build(BuildContext context) {
-    return Container();
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('扫一扫'),
+      ),
+    );
   }
 }