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У меня есть ошибка в приведенном ниже коде флаттера, когда я запускаю код, у меня возникает следующая ошибка, из-за чего это происходит? Я заявляю, что переключился на нулевую безопасность flutter 2. ошибка возникает при отображении виджета, с чем это может быть связано? код выполняет отображение карты с серией прокрутки виджетов местоположений на ней в определенной позиции, как можно решить эту проблему?

Ошибка:

 Another exception was thrown: Stack Overflow

Another exception was thrown: 'package:flutter/src/widgets/framework.dart': Failed assertion: line
4269 pos 14: 'owner!._debugCurrentBuildTarget == this': is not true.
 

Код Флаттера:

 import 'package:flutter/material.dart';
import 'package:google_maps_flutter/google_maps_flutter.dart';

class Coffee {
  final String shopName;
  final String address;
  final String description;
  final String thumbNail;
  final LatLng locationCoords;

  Coffee(
      {required this.shopName,
      required this.address,
      required this.description,
      required this.thumbNail,
      required this.locationCoords});
}

final List<Coffee> coffeeShops = [
  Coffee(
      shopName: 'Stumptown Coffee Roasters',
      address: '18 W 29th St',
      description:
          'Coffee bar chain offering house-roasted direct-trade coffee, along with brewing gear amp; whole beans',
      locationCoords: LatLng(40.745803, -73.988213),
      thumbNail:
          'https://lh5.googleusercontent.com/p/AF1QipNNzoa4RVMeOisc0vQ5m3Z7aKet5353lu0Aah0a=w90-h90-n-k-no'),
  Coffee(
      shopName: 'Andrews Coffee Shop',
      address: '463 7th Ave',
      description:
          'All-day American comfort eats in a basic diner-style setting',
      locationCoords: LatLng(40.751908, -73.989804),
      thumbNail:
          'https://lh5.googleusercontent.com/p/AF1QipOfv3DSTkjsgvwCsUe_flDr4DBXneEVR1hWQCvR=w90-h90-n-k-no'),
  Coffee(
      shopName: 'Third Rail Coffee',
      address: '240 Sullivan St',
      description:
          'Small spot draws serious caffeine lovers with wide selection of brews amp; baked goods.',
      locationCoords: LatLng(40.730148, -73.999639),
      thumbNail:
          'https://lh5.googleusercontent.com/p/AF1QipPGoxAP7eK6C44vSIx4SdhXdp78qiZz2qKp8-o1=w90-h90-n-k-no'),
  Coffee(
      shopName: 'Hi-Collar',
      address: '214 E 10th St',
      description:
          'Snazzy, compact Japanese cafe showcasing high-end coffee amp; sandwiches, plus sake amp; beer at night.',
      locationCoords: LatLng(40.729515, -73.985927),
      thumbNail:
          'https://lh5.googleusercontent.com/p/AF1QipNhygtMc1wNzN4n6txZLzIhgJ-QZ044R4axyFZX=w90-h90-n-k-no'),
  Coffee(
      shopName: 'Everyman Espresso',
      address: '301 W Broadway',
      description:
          'Compact coffee amp; espresso bar turning out drinks made from direct-trade beans in a low-key setting.',
      locationCoords: LatLng(40.721622, -74.004308),
      thumbNail:
          'https://lh5.googleusercontent.com/p/AF1QipOMNvnrTlesBJwUcVVFBqVF-KnMVlJMi7_uU6lZ=w90-h90-n-k-no')
];

class MapsScreenPage extends StatefulWidget {
  const MapsScreenPage({Key? key}) : super(key: key);

  @override
  _MapsScreenPageState createState() => _MapsScreenPageState();
}

class _MapsScreenPageState extends State<MapsScreenPage> {
  GoogleMapController? _controller;

  List<Marker> allMarkers = [];

  PageController _pageController = new PageController();

  int prevPage = 0;

  @override
  void initState() {
    super.initState();
    coffeeShops.forEach((element) {
      allMarkers.add(Marker(
          markerId: MarkerId(element.shopName),
          draggable: false,
          infoWindow:
              InfoWindow(title: element.shopName, snippet: element.address),
          position: element.locationCoords));
    });
    _pageController = PageController(initialPage: 1, viewportFraction: 0.8)
      ..addListener(_onScroll);
  }

  void _onScroll() {
    if (_pageController.page!.toInt() != prevPage) {
      prevPage = _pageController.page!.toInt();
      moveCamera();
    }
  }

  _coffeeShopList(index) {
    return AnimatedBuilder(
      animation: _pageController,
       builder: (BuildContext context, Widget? child) {
        double value = 1;
        if (_pageController.position.haveDimensions) {
          value = _pageController.page!.toDouble() - index.toDouble();
          value = (1 - (value.abs() * 0.3)   0.06).clamp(0.0, 1.0);
        }
        return Center(
          child: SizedBox(
            height: Curves.easeInOut.transform(value) * 125.0,
            width: Curves.easeInOut.transform(value) * 350.0,
            child: widget,
          ),
        );
      },
      child: InkWell(
          onTap: () {
            // moveCamera();
          },
          child: Stack(children: [
            Center(
                child: Container(
                    margin: EdgeInsets.symmetric(
                      horizontal: 10.0,
                      vertical: 20.0,
                    ),
                    height: 125.0,
                    width: 275.0,
                    decoration: BoxDecoration(
                        borderRadius: BorderRadius.circular(10.0),
                        boxShadow: [
                          BoxShadow(
                            color: Colors.black54,
                            offset: Offset(0.0, 4.0),
                            blurRadius: 10.0,
                          ),
                        ]),
                    child: Container(
                        decoration: BoxDecoration(
                            borderRadius: BorderRadius.circular(10.0),
                            color: Colors.white),
                        child: Row(children: [
                          Container(
                              height: 90.0,
                              width: 90.0,
                              decoration: BoxDecoration(
                                  borderRadius: BorderRadius.only(
                                      bottomLeft: Radius.circular(10.0),
                                      topLeft: Radius.circular(10.0)),
                                  image: DecorationImage(
                                      image: NetworkImage(
                                          coffeeShops[index].thumbNail),
                                      fit: BoxFit.cover))),
                          SizedBox(width: 5.0),
                          Column(
                              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                              crossAxisAlignment: CrossAxisAlignment.start,
                              children: [
                                Text(
                                  coffeeShops[index].shopName,
                                  style: TextStyle(
                                      fontSize: 12.5,
                                      fontWeight: FontWeight.bold),
                                ),
                                Text(
                                  coffeeShops[index].address,
                                  style: TextStyle(
                                      fontSize: 12.0,
                                      fontWeight: FontWeight.w600),
                                ),
                                Container(
                                  width: 170.0,
                                  child: Text(
                                    coffeeShops[index].description,
                                    style: TextStyle(
                                        fontSize: 11.0,
                                        fontWeight: FontWeight.w300),
                                  ),
                                )
                              ])
                        ]))))
          ])),
    );
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
                   home: Scaffold(
        body: FittedBox(
 fit: BoxFit.scaleDown,
 child:Stack(
      children: <Widget>[
        Container(
          height: MediaQuery.of(context).size.height,
          width: MediaQuery.of(context).size.width,
          child: GoogleMap(
            initialCameraPosition:
                CameraPosition(target: LatLng(40.7128, -74.0060), zoom: 12.0),
            markers: Set.from(allMarkers),
            onMapCreated: mapCreated,
          ),
        ),
        Positioned(
          bottom: 20.0,
          child: Container(
            height: 200.0,
            width: MediaQuery.of(context).size.width,
            child: PageView.builder(
              controller: _pageController,
              itemCount: coffeeShops.length,
              itemBuilder: (BuildContext context, int index) {
                return _coffeeShopList(index);
              },
            ),
          ),
        )
      ],
    )),
                   ),
    );
  }

  void mapCreated(controller) {
    setState(() {
      _controller = controller;
    });
  }

  moveCamera() {
    _controller?.animateCamera(CameraUpdate.newCameraPosition(CameraPosition(
        target: coffeeShops[_pageController.page!.toInt()].locationCoords,
        zoom: 14.0,
        bearing: 45.0,
        tilt: 45.0)));
  }
}