1、修改appbar

lib/widget/my_app_bar.dart

 import 'package:flutter/material.dart';
-import 'package:flutter/services.dart';
 
 class MyPageAppBar extends StatelessWidget implements PreferredSizeWidget {
   final String? title;
@@ -29,22 +28,6 @@ class MyPageAppBar extends StatelessWidget implements PreferredSizeWidget {
       title: Text(title ?? ""),
       backgroundColor: backgroundColor,
       primary: primary,
-      leading: showBack
-          ? InkWell(
-              onTap: onBack ??
-                  () {
-                    if (exitApp) {
-                      SystemNavigator.pop();
-                    } else {
-                      Navigator.pop(context);
-                    }
-                  },
-              child: const Icon(
-                Icons.arrow_back_ios,
-                color: Colors.white,
-              ),
-            )
-          : null,
       actions: actions,
     );
   }