completed group batch feature

lib/abstracts/AbstractController.dart

@@ -1,17 +1,12 @@
 import 'package:flutter/material.dart';
+import 'package:qpay/widgets/app_snack_bar.dart';
 
 class AbstractController extends ChangeNotifier {
   late BuildContext context;
   void showErrorSnackBar(String? message) {
     WidgetsBinding.instance.addPostFrameCallback((_) {
-      ScaffoldMessenger.of(context).showSnackBar(
-        SnackBar(
-          content: Text(message.toString()),
-          behavior: SnackBarBehavior.floating,
-          backgroundColor: Colors.deepOrange,
-        ),
-      );
+      AppSnackBar.showError(context, message.toString());
     });
   }
 
-}
+}