Snapshot empty after successful API call, Flutter-CodePudding

I'm making a simple app with Star Wars data and I keep getting snapshot data is null, the only thing that comes to mind is that I'm not populating the model correctly and I can't seem to find the solution to this problem. The code:

Model:

class PeopleModel {
  String? name;
  String? height;
  String? mass;
  String? hairColor;
  String? skinColor;
  String? eyeColor;
  String? birthYear;
  String? gender;
  String? homeworld;
  List<String>? films;
  List<String>? species;
  List<String>? vehicles;
  List<String>? starships;
  String? created;
  String? edited;
  String? url;

  PeopleModel(
      {this.name,
      this.height,
      this.mass,
      this.hairColor,
      this.skinColor,
      this.eyeColor,
      this.birthYear,
      this.gender,
      this.homeworld,
      this.films,
      this.species,
      this.vehicles,
      this.starships,
      this.created,
      this.edited,
      this.url});

  PeopleModel.fromJson(Map<String, dynamic> json) {
    name = json['name'];
    height = json['height'];
    mass = json['mass'];
    hairColor = json['hair_color'];
    skinColor = json['skin_color'];
    eyeColor = json['eye_color'];
    birthYear = json['birth_year'];
    gender = json['gender'];
    homeworld = json['homeworld'];
    films = json['films'].cast<String>();
    species = json['species'].cast<String>();
    vehicles = json['vehicles'].cast<String>();
    starships = json['starships'].cast<String>();
    created = json['created'];
    edited = json['edited'];
    url = json['url'];
  }

  Map<String, dynamic> toJson() {
    final Map<String, dynamic> data = <String, dynamic>{};
    data['name'] = name;
    data['height'] = height;
    data['mass'] = mass;
    data['hair_color'] = hairColor;
    data['skin_color'] = skinColor;
    data['eye_color'] = eyeColor;
    data['birth_year'] = birthYear;
    data['gender'] = gender;
    data['homeworld'] = homeworld;
    data['films'] = films;
    data['species'] = species;
    data['vehicles'] = vehicles;
    data['starships'] = starships;
    data['created'] = created;
    data['edited'] = edited;
    data['url'] = url;
    return data;
  }
}

Store for the provider model:

import 'package:flutter/foundation.dart';

class PeopleStore extends ChangeNotifier {
  bool _loading = false;

  Map<String?, PeopleModel> _people = {};

  bool getLoading() => _loading;

  void setLoading(bool loading) {
    _loading = loading;
    notifyListeners();
  }

  void setPeople(Map<String?, PeopleModel> people) {
    _people = people;
    notifyListeners();
  }

  Map<String?, PeopleModel>? getPeople() => _people;
}

The Api call:

Future<HTTPResponse<Map<String?, PeopleModel>>> getPeople() async {
    final response = await (SWHttpProvider.apiRequest(Method.GET, 'people'));

    dynamic body = jsonDecode(utf8.decode(response!.bodyBytes));
    if (response.statusCode == 200) {
      dynamic data = body['results'] as List?;
      Map<String?, PeopleModel> peopleMap = {};
      data.forEach((peopleData) {
        PeopleModel people = PeopleModel.fromJson(peopleData);
        peopleMap[people.name] = people ;
      });
      return HTTPResponse<Map<String?, PeopleModel>>(
        isSuccessful: true,
        data: peopleMap,
        message: HTTPResponse.successMessage,
        statusCode: response.statusCode,
      );
    } else {
      return HTTPResponse<Map<String?, PeopleModel>>(
        isSuccessful: false,
        data: null,
        message: body['message'] ?? HTTPResponse.errorMessage,
        statusCode: response.statusCode,
      );
    }
  }

The API JSON data:

https://swapi.dev/api/people/ /// the URL for the API

{
    "count": 82, 
    "next": "https://swapi.dev/api/people/?page=2", 
    "previous": null, 
    "results": [
        {
            "name": "Luke Skywalker", 
            "height": "172", 
            "mass": "77", 
            "hair_color": "blond", 
            "skin_color": "fair", 
            "eye_color": "blue", 
            "birth_year": "19BBY", 
            "gender": "male", 
            "homeworld": "https://swapi.dev/api/planets/1/", 
            "films": [
                "https://swapi.dev/api/films/1/", 
                "https://swapi.dev/api/films/2/", 
                "https://swapi.dev/api/films/3/", 
                "https://swapi.dev/api/films/6/"
            ], 
            "species": [], 
            "vehicles": [
                "https://swapi.dev/api/vehicles/14/", 
                "https://swapi.dev/api/vehicles/30/"
            ], 
            "starships": [
                "https://swapi.dev/api/starships/12/", 
                "https://swapi.dev/api/starships/22/"
            ], 
            "created": "2014-12-09T13:50:51.644000Z", 
            "edited": "2014-12-20T21:17:56.891000Z", 
            "url": "https://swapi.dev/api/people/1/"
        }, 
        {
            "name": "C-3PO", 
            "height": "167", 
            "mass": "75", 
            "hair_color": "n/a", 
            "skin_color": "gold", 
            "eye_color": "yellow", 
            "birth_year": "112BBY", 
            "gender": "n/a", 
            "homeworld": "https://swapi.dev/api/planets/1/", 
            "films": [
                "https://swapi.dev/api/films/1/", 
                "https://swapi.dev/api/films/2/", 
                "https://swapi.dev/api/films/3/", 
                "https://swapi.dev/api/films/4/", 
                "https://swapi.dev/api/films/5/", 
                "https://swapi.dev/api/films/6/"
            ], 
            "species": [
                "https://swapi.dev/api/species/2/"
            ], 
            "vehicles": [], 
            "starships": [], 
            "created": "2014-12-10T15:10:51.357000Z", 
            "edited": "2014-12-20T21:17:50.309000Z", 
            "url": "https://swapi.dev/api/people/2/"
        }, 
        {
            "name": "R2-D2", 
            "height": "96", 
            "mass": "32", 
            "hair_color": "n/a", 
            "skin_color": "white, blue", 
            "eye_color": "red", 
            "birth_year": "33BBY", 
            "gender": "n/a", 
            "homeworld": "https://swapi.dev/api/planets/8/", 
            "films": [
                "https://swapi.dev/api/films/1/", 
                "https://swapi.dev/api/films/2/", 
                "https://swapi.dev/api/films/3/", 
                "https://swapi.dev/api/films/4/", 
                "https://swapi.dev/api/films/5/", 
                "https://swapi.dev/api/films/6/"
            ], 
            "species": [
                "https://swapi.dev/api/species/2/"
            ], 
            "vehicles": [], 
            "starships": [], 
            "created": "2014-12-10T15:11:50.376000Z", 
            "edited": "2014-12-20T21:17:50.311000Z", 
            "url": "https://swapi.dev/api/people/3/"
        }, 
        {
            "name": "Darth Vader", 
            "height": "202", 
            "mass": "136", 
            "hair_color": "none", 
            "skin_color": "white", 
            "eye_color": "yellow", 
            "birth_year": "41.9BBY", 
            "gender": "male", 
            "homeworld": "https://swapi.dev/api/planets/1/", 
            "films": [
                "https://swapi.dev/api/films/1/", 
                "https://swapi.dev/api/films/2/", 
                "https://swapi.dev/api/films/3/", 
                "https://swapi.dev/api/films/6/"
            ], 
            "species": [], 
            "vehicles": [], 
            "starships": [
                "https://swapi.dev/api/starships/13/"
            ], 
            "created": "2014-12-10T15:18:20.704000Z", 
            "edited": "2014-12-20T21:17:50.313000Z", 
            "url": "https://swapi.dev/api/people/4/"
        }, 
        {
            "name": "Leia Organa", 
            "height": "150", 
            "mass": "49", 
            "hair_color": "brown", 
            "skin_color": "light", 
            "eye_color": "brown", 
            "birth_year": "19BBY", 
            "gender": "female", 
            "homeworld": "https://swapi.dev/api/planets/2/", 
            "films": [
                "https://swapi.dev/api/films/1/", 
                "https://swapi.dev/api/films/2/", 
                "https://swapi.dev/api/films/3/", 
                "https://swapi.dev/api/films/6/"
            ], 
            "species": [], 
            "vehicles": [
                "https://swapi.dev/api/vehicles/30/"
            ], 
            "starships": [], 
            "created": "2014-12-10T15:20:09.791000Z", 
            "edited": "2014-12-20T21:17:50.315000Z", 
            "url": "https://swapi.dev/api/people/5/"
        }, 
        {
            "name": "Owen Lars", 
            "height": "178", 
            "mass": "120", 
            "hair_color": "brown, grey", 
            "skin_color": "light", 
            "eye_color": "blue", 
            "birth_year": "52BBY", 
            "gender": "male", 
            "homeworld": "https://swapi.dev/api/planets/1/", 
            "films": [
                "https://swapi.dev/api/films/1/", 
                "https://swapi.dev/api/films/5/", 
                "https://swapi.dev/api/films/6/"
            ], 
            "species": [], 
            "vehicles": [], 
            "starships": [], 
            "created": "2014-12-10T15:52:14.024000Z", 
            "edited": "2014-12-20T21:17:50.317000Z", 
            "url": "https://swapi.dev/api/people/6/"
        }, 
        {
            "name": "Beru Whitesun lars", 
            "height": "165", 
            "mass": "75", 
            "hair_color": "brown", 
            "skin_color": "light", 
            "eye_color": "blue", 
            "birth_year": "47BBY", 
            "gender": "female", 
            "homeworld": "https://swapi.dev/api/planets/1/", 
            "films": [
                "https://swapi.dev/api/films/1/", 
                "https://swapi.dev/api/films/5/", 
                "https://swapi.dev/api/films/6/"
            ], 
            "species": [], 
            "vehicles": [], 
            "starships": [], 
            "created": "2014-12-10T15:53:41.121000Z", 
            "edited": "2014-12-20T21:17:50.319000Z", 
            "url": "https://swapi.dev/api/people/7/"
        }, 
        {
            "name": "R5-D4", 
            "height": "97", 
            "mass": "32", 
            "hair_color": "n/a", 
            "skin_color": "white, red", 
            "eye_color": "red", 
            "birth_year": "unknown", 
            "gender": "n/a", 
            "homeworld": "https://swapi.dev/api/planets/1/", 
            "films": [
                "https://swapi.dev/api/films/1/"
            ], 
            "species": [
                "https://swapi.dev/api/species/2/"
            ], 
            "vehicles": [], 
            "starships": [], 
            "created": "2014-12-10T15:57:50.959000Z", 
            "edited": "2014-12-20T21:17:50.321000Z", 
            "url": "https://swapi.dev/api/people/8/"
        }, 
        {
            "name": "Biggs Darklighter", 
            "height": "183", 
            "mass": "84", 
            "hair_color": "black", 
            "skin_color": "light", 
            "eye_color": "brown", 
            "birth_year": "24BBY", 
            "gender": "male", 
            "homeworld": "https://swapi.dev/api/planets/1/", 
            "films": [
                "https://swapi.dev/api/films/1/"
            ], 
            "species": [], 
            "vehicles": [], 
            "starships": [
                "https://swapi.dev/api/starships/12/"
            ], 
            "created": "2014-12-10T15:59:50.509000Z", 
            "edited": "2014-12-20T21:17:50.323000Z", 
            "url": "https://swapi.dev/api/people/9/"
        }, 
        {
            "name": "Obi-Wan Kenobi", 
            "height": "182", 
            "mass": "77", 
            "hair_color": "auburn, white", 
            "skin_color": "fair", 
            "eye_color": "blue-gray", 
            "birth_year": "57BBY", 
            "gender": "male", 
            "homeworld": "https://swapi.dev/api/planets/20/", 
            "films": [
                "https://swapi.dev/api/films/1/", 
                "https://swapi.dev/api/films/2/", 
                "https://swapi.dev/api/films/3/", 
                "https://swapi.dev/api/films/4/", 
                "https://swapi.dev/api/films/5/", 
                "https://swapi.dev/api/films/6/"
            ], 
            "species": [], 
            "vehicles": [
                "https://swapi.dev/api/vehicles/38/"
            ], 
            "starships": [
                "https://swapi.dev/api/starships/48/", 
                "https://swapi.dev/api/starships/59/", 
                "https://swapi.dev/api/starships/64/", 
                "https://swapi.dev/api/starships/65/", 
                "https://swapi.dev/api/starships/74/"
            ], 
            "created": "2014-12-10T16:16:29.192000Z", 
            "edited": "2014-12-20T21:17:50.325000Z", 
            "url": "https://swapi.dev/api/people/10/"
        }
    ]
}

Actions providing the data to the model:

Future<void> fetchPeople() async {
    final peopleRes = await peopleApi.getPeople();

    if (peopleRes.isSuccessful!) {
      peopleStore.setPeople(peopleRes.data!);
    }
  }

The returning data from the FutureBuilder is always 'Empty Data':

FutureBuilder(
          future: PeopleActions(context).fetchPeople(),
          builder: (BuildContext context, AsyncSnapshot snapshot) {
            if (snapshot.connectionState == ConnectionState.waiting) {
              return const Center(child: CircularProgressIndicator());
            } else if (snapshot.connectionState == ConnectionState.done) {
              if (snapshot.hasError) {
                return const Text('Error');
              } else if (snapshot.hasData) {
                return ListView.builder(
                    itemCount: 5,
                    itemBuilder: (BuildContext context, int index) {
                      final data =
                          Provider.of<PeopleStore>(context, listen: false)
                              .getPeople();
                      return Text('${data![index]?.name} $index');
                    });
              } else {
                return const Text('Empty data');
              }
            } else {
              return Text('State: ${snapshot.connectionState}');
            }
          },
        ),

Thanks in advance for your help!

CodePudding user response：

You need to return something in your FutureBuilder's future in order to snapshot has data, so change your fetchPeople() to this:

Future<Map<String?, PeopleModel>> fetchPeople() async {
    final peopleRes = await peopleApi.getPeople();

    if (peopleRes.isSuccessful!) {
      peopleStore.setPeople(peopleRes.data!); 
      return peopleRes.data!;
    }else {
      return {};
    }
  }