Exception in type cast dart

Question

Запутался в type cast, помогите разобраться. Исключение: I/flutter ( 9296): Exception: type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'List<dynamic>' in type cast

Сам код:

import 'package:flutter/material.dart';
import 'package:practice_5/model/breedModel.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';
import 'dart:async';
import 'package:flutter/foundation.dart';

Future<List<Dog>> fetchPhotos(http.Client client) async {
  final response =
  await client.get('https://dog.ceo/api/breeds/image/random');
  return compute(parseDog, response.body);
}

List<Dog> parseDog(responseBody) {
  final parsed = jsonDecode(responseBody) as List;
  return parsed.map<Dog>((json) => Dog.fromJson(json)).toList();
}

class BreedListTile extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return FutureBuilder<List<Dog>>(
      future: fetchPhotos(http.Client()),
      builder: (context, snapshot) {
        if (snapshot.hasError) print(snapshot.error);
        return snapshot.hasData
            ? DogListTile (dogs: snapshot.data,)
            : Center (child: CircularProgressIndicator());
      },
    );
  }
}

class DogListTile extends StatelessWidget {
  final List<Dog> dogs;

  DogListTile({Key key, this.dogs}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return ListView.builder(
        itemCount: dogs.length,
        itemBuilder: (context, index) {
          return ListTile (
            title: Text ('Title'),
            subtitle: Text ('Subtitle'),
            leading: Image.network(dogs[index].message),
          );
        });
  }
}

Answer 1

Каст не правильный final parsed = jsonDecode(responseBody) as List;, откуда вы взяли List?

Вот решение:

import 'dart:convert';

Dog dogFromJson(String str) => Dog.fromJson(json.decode(str));

String dogToJson(Dog data) => json.encode(data.toJson());

class Dog {
    Dog({
        this.message,
        this.status,
    });

    final String message;
    final String status;

    factory Dog.fromJson(Map<String, dynamic> json) => Dog(
        message: json["message"] == null ? null : json["message"],
        status: json["status"] == null ? null : json["status"],
    );

    Map<String, dynamic> toJson() => {
        "message": message == null ? null : message,
        "status": status == null ? null : status,
    };
}

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Exception in type cast dart

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