no message

lib/main.dart

@@ -56,6 +56,16 @@ void main() async {
         GlobalWidgetsLocalizations.delegate,
         GlobalCupertinoLocalizations.delegate, // iOS
       ],
+      theme: ThemeData(
+        scaffoldBackgroundColor: Colors.white,
+        // 设置导航栏样式
+        appBarTheme: AppBarTheme(
+          systemOverlayStyle: SystemUiOverlayStyle(
+            systemNavigationBarColor: Colors.white,
+            systemNavigationBarIconBrightness: Brightness.light,
+          ),
+        ),
+      ),
       builder: FlutterSmartDialog.init(),
       home: MyApp(),
     ),