I received this error when I run the project. I am using a JSON API from https://rapidapi.com/apidojo/api/yummly2.

This is error I got, Error: NoSuchMethodError: 'call' Dynamic call of object has no instance method 'call'. Receiver: Instance of '_JsonMap' Arguments: ["name"]

I don't understand why I can get the error, because there are no red lines on my code.

api_recipe.dart

import 'package:deliciouso/model/recipe.dart';
import 'package:http/http.dart' as http;
import 'package:deliciouso/model/api_recipe.dart';

class ApiRecipe {


  static Future<List<Recipe>> getRecipe() async {
    var uri = Uri.https('yummly2.p.rapidapi.com', '/feeds/list',
        {"start": "0", "limit": "18", "tag": "list.recipe.popular"});

    final response = await http.get(uri, headers: {
      "x-rapidapi-key": "659d1b868cmsh981c45e6fe4147fp12524fjsna4689c3a42f3",
      "x-rapidapi-host": "yummly2.p.rapidapi.com",     
      "useQueryString": "true"
    });

    Map data = jsonDecode(response.body);

    List _temp = [];

    for(var i in data['feed']){
      _temp.add(i['content']['details']);
    }
    return Recipe.recipeFromSnapshot(_temp);
    
  }
}

recipe.dart

  final String name;
  final String img;
  final double rating;
  final String time;

  Recipe(
      {required this.name,
      required this.img,
      required this.rating,
      required this.time});

  factory Recipe.fromJson(dynamic json) {
    return Recipe(
        name: json('name') as String,
        img: json('img')[0]['hostedLargeURL'] as String,
        rating: json('rating') as double,
        time: json('time') as String);
  }

  static List<Recipe> recipeFromSnapshot(List snapshot) {
    return snapshot.map((data) {
      return Recipe.fromJson(data);
    }).toList();
  }

  @override
  String toString() {
   
    return 'Recipe {name: $name, img: $img, rating: $rating, time: $time}';
  }
}

recipe_card.dart

class RecipeCard extends StatelessWidget {
  final String title;
  final String rating;
  final String cookTime;
  final String url;

  const RecipeCard(
      {required this.title,
      required this.rating,
      required this.cookTime,
      required this.url});

  @override
  Widget build(BuildContext context) {
    return Container(
      margin: EdgeInsets.symmetric(horizontal: 22, vertical: 10),
      width: MediaQuery.of(context).size.width,
      height: 250,
      decoration: BoxDecoration(
        color: Colors.black,
        borderRadius: BorderRadius.circular(15),
        boxShadow: [
          BoxShadow(
              color: Colors.black.withOpacity(0.6),
              offset: Offset(0.0, 10.0),
              blurRadius: 10.0,
              spreadRadius: -6.0),
        ],
        image: DecorationImage(
            colorFilter: ColorFilter.mode(
                Colors.black.withOpacity(0.35), BlendMode.multiply),
            image: NetworkImage(url),
            fit: BoxFit.cover),
      ),
      child: Stack(
        children: [
          Align(
            child: Padding(
              padding: EdgeInsets.symmetric(horizontal: 5.0),
              child: Text(title,
                  style: TextStyle(fontSize: 19),
                  overflow: TextOverflow.ellipsis,
                  maxLines: 2,
                  textAlign: TextAlign.center),
            ),
            alignment: Alignment.center,
          ),
          Align(
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Container(
                  padding: EdgeInsets.all(5),
                  margin: EdgeInsets.all(10),
                  decoration: BoxDecoration(
                      color: Colors.black.withOpacity(0.4),
                      borderRadius: BorderRadius.circular(15)),
                  child: Row(
                    children: [
                      Icon(
                        Icons.stars,
                        color: Colors.yellow,
                        size: 18,
                      ),
                      SizedBox(
                        width: 7,
                      ),
                      Text(rating),
                    ],
                  ),
                ),
                Container(
                  padding: EdgeInsets.all(5),
                  margin: EdgeInsets.all(10),
                  decoration: BoxDecoration(
                      color: Colors.black.withOpacity(0.4),
                      borderRadius: BorderRadius.circular(15)),
                  child: Row(
                    children: [
                      Icon(
                        Icons.schedule,
                        color: Colors.yellow,
                        size: 18,
                      ),
                      SizedBox(
                        width: 7,
                      ),
                      Text(cookTime),
                    ],
                  ),
                ),
              ],
            ),
            alignment: Alignment.bottomLeft,
          )
        ],
      ),
    );
  }
}

home.dart

import 'package:deliciouso/screens/widget/recipe_card.dart';
import 'package:flutter/material.dart';
import 'package:deliciouso/model/recipe.dart';

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

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

class _HomeState extends State<Home> {
  late List<Recipe> _recipe;
  bool _isLoading = true;

  @override
  void initState() {
    super.initState();
    getRecipe();
  }

  Future<void> getRecipe() async {
    _recipe = await ApiRecipe.getRecipe();
    setState(() {
      _isLoading = false;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Row(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              Icon(Icons.restaurant_menu),
              SizedBox(width: 10),
              Text('Food Recipes')
            ],
          ),
        ),
        body: _isLoading
            ? Center(child: CircularProgressIndicator())
            : ListView.builder(
                itemCount: _recipe.length,
                itemBuilder: (context, index) {
                  return RecipeCard(
                    title: _recipe[index].name,
                    cookTime: _recipe[index].time,
                    rating: _recipe[index].rating.toString(),
                    url: _recipe[index].img,
                  );
                },
              ));
  }
}

main.dart

import 'package:flutter/material.dart';


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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Delicioso',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
          primarySwatch: Colors.blue,
          primaryColor: Colors.white,
          textTheme: TextTheme(bodyText2: TextStyle(color: Colors.white))),
      home: Home(),
    );
  }
}

CodePudding user response：

Your Recipe.fromJson method has some incorrect syntax. When accessing the members of a Map, use the [] operator. Do not use () as you are doing currently.

factory Recipe.fromJson(dynamic json) {
    return Recipe(
        name: json['name'] as String,
        img: json['img'][0]['hostedLargeURL'] as String,
        rating: json['rating'] as double,
        time: json['time'] as String);
}

() will try to invoke the call method of an object, which your object does not have, which is why you get the error "call of object has no instance method 'call'"