小编Tom*_*tiz的帖子

我希望你能帮助我。我正在尝试使用新方法来显示带有 ScaffoldMessenger 而不是 Scaffold 的 SnackBar。当我尝试运行它时，我遇到了这个问题：

======== Exception caught by gesture ===============================================================
The following NoSuchMethodError was thrown while handling a gesture:
The method 'showSnackBar' was called on null.
Receiver: null
Tried calling: showSnackBar(Instance of 'SnackBar')

这是我的代码：

import 'package:cab_rider/screens/loginpage.dart';
import 'package:cab_rider/widgets/TaxiButton.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';

class RegistrationPage extends StatelessWidget {

  static const String id = 'register';

  var NombresController = TextEditingController();
  var ApePaternoController = TextEditingController();
  var ApeMaternoController= TextEditingController();
  var EmailController = TextEditingController();
  var TelefonoController = TextEditingController();
  var PasswordController = TextEditingController(); …