android – How you can resolve no Navigator in Context error in Flutter Dart

I’m attempting to vary display on push button. However by some means the context has no Navigator because the error suggests:

Navigator operation requested with a context that doesn't embody a Navigator.

The context used to push or pop routes from the Navigator have to be that of a widget that may be a descendant of a Navigator widget.
When the exception was thrown, this was the stack: 
#0      Navigator.of.<nameless closure> (package deal:flutter/src/widgets/navigator.dart:2554:9)
#1      Navigator.of (package deal:flutter/src/widgets/navigator.dart:2561:6)
#2      _MyAppState.construct.<nameless closure>.<nameless closure> (package deal:base_app/principal.dart:64:35)
#3      _InkResponseState.handleTap (package deal:flutter/src/materials/ink_well.dart:1072:21)
#4      GestureRecognizer.invokeCallback (package deal:flutter/src/gestures/recognizer.dart:253:24)
#5      TapGestureRecognizer.handleTapUp (package deal:flutter/src/gestures/faucet.dart:627:11)
#6      BaseTapGestureRecognizer._checkUp (package deal:flutter/src/gestures/faucet.dart:306:5)
#7      BaseTapGestureRecognizer.handlePrimaryPointer (package deal:flutter/src/gestures/faucet.dart:239:7)

Nonetheless, in response to this message there’s a Navigator in #0 and #1 so what’s the drawback?

Mycode:

import 'package deal:amplify_auth_cognito/amplify_auth_cognito.dart';
import 'package deal:amplify_authenticator/amplify_authenticator.dart';
import 'package deal:amplify_flutter/amplify_flutter.dart';
import 'package deal:flutter/materials.dart';

import 'package deal:base_app/add_device.dart';

import 'amplifyconfiguration.dart';

void principal() {
  runApp(const MyApp());
}

class MyApp extends StatefulWidget {
  const MyApp({Key? key}) : tremendous(key: key);

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  bool _isAmplifyConfigured = false;

  @override
  void initState() {
    tremendous.initState();
    _configureAmplify();
  }

  void _configureAmplify() async {
    strive {
      await Amplify.addPlugin(AmplifyAuthCognito());
      await Amplify.configure(amplifyconfig);
      setState(() => _isAmplifyConfigured = true);
      print('Efficiently configured');
    } on Exception catch (e) {
      print('Error configuring Amplify: $e');
    }
  }

  Future<bool> isUserSignedIn() async {
    last consequence = await Amplify.Auth.fetchAuthSession();
    return consequence.isSignedIn;
  }

  @override
  Widget construct(BuildContext context) {
    return Authenticator(
      baby: MaterialApp(
        builder: Authenticator.builder(),
        dwelling: _isAmplifyConfigured? FutureBuilder(
            future: isUserSignedIn(),
            builder: (BuildContext ctx, AsyncSnapshot snapshot) {
              if (snapshot.knowledge == null) {
                return const Heart(
                  baby: CircularProgressIndicator(),
                );
              } else {
                return Scaffold(
                    floatingActionButton: FloatingActionButton(
                      backgroundColor: Colours.blue,
                      foregroundColor: Colours.white,
                      onPressed: () => {
                        Navigator.of(context).push(
                            MaterialPageRoute(builder: (context) => AddDevice())),

                      },
                      baby: Icon(Icons.add),
                    )
                );
              }
            }): Textual content("not logged in")
      ),
    );
  }
}

It is a fundamental code of a extra advanced app however even right here it doesn’t work. I attempted a number of strategies from different posts with all the identical consequence.