How to use model in flutter-CodePudding

I am storing json object in a model and trying to access properties of my model but I am not able to access my properties which is in my model following is my json object which I am storing in model

{
    "statusCode": 200,
    "success": true,
    "messages": [],
    "data": [
        {
            "id": 35,
            "title": "Astrology",
            "filename": "Astrology.jpg",
            "mimetype": "image/jpeg",
            "directcalling": 1,
            "parentid": null,
            "subcat": [
                {
                    "id": 53,
                    "title": "vgb",
                    "filename": "vgb.jpg",
                    "mimetype": "image/jpeg",
                    "directcalling": 0,
                    "parentid": 35,
                    "subcat": []
                }
            ]
        },
        {
            "id": 36,
            "title": "Muhurtam",
            "filename": "Muhurtam.jpg",
            "mimetype": "image/jpeg",
            "directcalling": 1,
            "parentid": null,
            "subcat": [
                {
                    "id": 50,
                    "title": "abc",
                    "filename": "abc.png",
                    "mimetype": "image/png",
                    "directcalling": 0,
                    "parentid": 36,
                    "subcat": []
                }
            ]
        },
        {
            "id": 37,
            "title": "DharamSandhehalu",
            "filename": "DharamSandhehalu.jpg",
            "mimetype": "image/jpeg",
            "directcalling": 1,
            "parentid": null,
            "subcat": []
        },
        {
            "id": 38,
            "title": "Allpoojas",
            "filename": "Allpoojas.jpg",
            "mimetype": "image/jpeg",
            "directcalling": 0,
            "parentid": null,
            "subcat": [
                {
                    "id": 40,
                    "title": "gugu",
                    "filename": "gugu.png",
                    "mimetype": "image/png",
                    "directcalling": 0,
                    "parentid": 38,
                    "subcat": []
                }
                
            ]
        }
    ]
}

following is my model class where I am storing my json object

class Categories {
  Categories({
    required this.statusCode,
    required this.success,
    required this.messages,
    required this.data,
  });
  late final int statusCode;
  late final bool success;
  late final List<dynamic> messages;
  late final List<Data> data;

  Categories.fromJson(Map<String, dynamic> json) {
    statusCode = json['statusCode'];
    success = json['success'];
    messages = List.castFrom<dynamic, dynamic>(json['messages']);
    data = List.from(json['data']).map((e) => Data.fromJson(e)).toList();
  }

  Map<String, dynamic> toJson() {
    final _data = <String, dynamic>{};
    _data['statusCode'] = statusCode;
    _data['success'] = success;
    _data['messages'] = messages;
    _data['data'] = data.map((e) => e.toJson()).toList();
    return _data;
  }
}

class Data {
  Data({
    required this.id,
    required this.title,
    required this.filename,
    required this.mimetype,
    required this.directcalling,
    this.parentid,
    required this.subcat,
  });
  late final int id;
  late final String title;
  late final String filename;
  late final String mimetype;
  late final int directcalling;
  late final Null parentid;
  late final List<Subcat> subcat;

  Data.fromJson(Map<String, dynamic> json) {
    id = json['id'];
    title = json['title'];
    filename = json['filename'];
    mimetype = json['mimetype'];
    directcalling = json['directcalling'];
    parentid = null;
    subcat = List.from(json['subcat']).map((e) => Subcat.fromJson(e)).toList();
  }

  Map<String, dynamic> toJson() {
    final _data = <String, dynamic>{};
    _data['id'] = id;
    _data['title'] = title;
    _data['filename'] = filename;
    _data['mimetype'] = mimetype;
    _data['directcalling'] = directcalling;
    _data['parentid'] = parentid;
    _data['subcat'] = subcat.map((e) => e.toJson()).toList();
    return _data;
  }
}

class Subcat {
  Subcat({
    required this.id,
    required this.title,
    required this.filename,
    required this.mimetype,
    required this.directcalling,
    required this.parentid,
    required this.subcat,
  });
  late final int id;
  late final String title;
  late final String filename;
  late final String mimetype;
  late final int directcalling;
  late final int parentid;
  late final List<dynamic> subcat;

  Subcat.fromJson(Map<String, dynamic> json) {
    id = json['id'];
    title = json['title'];
    filename = json['filename'];
    mimetype = json['mimetype'];
    directcalling = json['directcalling'];
    parentid = json['parentid'];
    subcat = List.castFrom<dynamic, dynamic>(json['subcat']);
  }

  Map<String, dynamic> toJson() {
    final _data = <String, dynamic>{};
    _data['id'] = id;
    _data['title'] = title;
    _data['filename'] = filename;
    _data['mimetype'] = mimetype;
    _data['directcalling'] = directcalling;
    _data['parentid'] = parentid;
    _data['subcat'] = subcat;
    return _data;
  }
}

following is my api where I am getting response and storing in my model

Future<void> getCatogories(BuildContext cont) async {
    final url = PurohitApi().baseUrl   PurohitApi().getcatogory;

    try {
      var response = await http.get(
        Uri.parse(url),
        headers: {
          'Content-Type': 'application/json; charset=UTF-8',
        },
      );
      Map<String, dynamic> categoryTypes = json.decode(response.body);
      if (categoryTypes['data'] != null) {
        categories = categoryTypes['data'];
      }
      categorieModel = Categories.fromJson(categoryTypes);
      print(sample!.filename);

      notifyListeners();
    } catch (e) {
      print(e);
    }
  }

now I am trying to access list which is in categories class which I am not getting how to do

CodePudding user response：

Try following demo

import 'package: flutter/material.dart';
import 'dart:convert';
const Color darkBlue = Color.fromARGB(255, 18, 32, 47);

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

class MyApp extends StatelessWidget {
  


  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData.dark().copyWith(
        scaffoldBackgroundColor: darkBlue,
      ),
      debugShowCheckedModeBanner: false,
      home: Scaffold(
        body: Center(
          child: MyWidget(),
        ),
      ),
    );
  }
}

class MyWidget extends StatelessWidget {
  
  
    String jsonString = "{"  
"    \"statusCode\": 200,"  
"    \"success\": true,"  
"    \"messages\": [],"  
"    \"data\": ["  
"        {"  
"            \"id\": 35,"  
"            \"title\": \"Astrology\","  
"            \"filename\": \"Astrology.jpg\","  
"            \"mimetype\": \"image/jpeg\","  
"            \"directcalling\": 1,"  
"            \"parentid\": null,"  
"            \"subcat\": ["  
"                {"  
"                    \"id\": 53,"  
"                    \"title\": \"vgb\","  
"                    \"filename\": \"vgb.jpg\","  
"                    \"mimetype\": \"image/jpeg\","  
"                    \"directcalling\": 0,"  
"                    \"parentid\": 35,"  
"                    \"subcat\": []"  
"                }"  
"            ]"  
"        },"  
"        {"  
"            \"id\": 36,"  
"            \"title\": \"Muhurtam\","  
"            \"filename\": \"Muhurtam.jpg\","  
"            \"mimetype\": \"image/jpeg\","  
"            \"directcalling\": 1,"  
"            \"parentid\": null,"  
"            \"subcat\": ["  
"                {"  
"                    \"id\": 50,"  
"                    \"title\": \"abc\","  
"                    \"filename\": \"abc.png\","  
"                    \"mimetype\": \"image/png\","  
"                    \"directcalling\": 0,"  
"                    \"parentid\": 36,"  
"                    \"subcat\": []"  
"                }"  
"            ]"  
"        },"  
"        {"  
"            \"id\": 37,"  
"            \"title\": \"DharamSandhehalu\","  
"            \"filename\": \"DharamSandhehalu.jpg\","  
"            \"mimetype\": \"image/jpeg\","  
"            \"directcalling\": 1,"  
"            \"parentid\": null,"  
"            \"subcat\": []"  
"        },"  
"        {"  
"            \"id\": 38,"  
"            \"title\": \"Allpoojas\","  
"            \"filename\": \"Allpoojas.jpg\","  
"            \"mimetype\": \"image/jpeg\","  
"            \"directcalling\": 0,"  
"            \"parentid\": null,"  
"            \"subcat\": ["  
"                {"  
"                    \"id\": 40,"  
"                    \"title\": \"gugu\","  
"                    \"filename\": \"gugu.png\","  
"                    \"mimetype\": \"image/png\","  
"                    \"directcalling\": 0,"  
"                    \"parentid\": 38,"  
"                    \"subcat\": []"  
"                }"  
"                "  
"            ]"  
"        }"  
"    ]"  
"}";
  
  @override
  Widget build(BuildContext context) {
    return 
      ListView.builder(
          itemCount: Categories.fromJson(json.decode(jsonString)).data.length,
          itemBuilder: (BuildContext context, int index) {
            return ListTile(
                leading: const Icon(Icons.list),
                trailing:  Text(
                  (Categories.fromJson(json.decode(jsonString)).data[index].subcat.length.toString()),
                  style: TextStyle(color: Colors.green, fontSize: 15),
                ),
                title: Text((Categories.fromJson(json.decode(jsonString)).data[index].title)));
          });
     
  }
}


class Categories {
  Categories({
    required this.statusCode,
    required this.success,
    required this.messages,
    required this.data,
  });
  late final int statusCode;
  late final bool success;
  late final List<dynamic> messages;
  late final List<Data> data;

  Categories.fromJson(Map<String, dynamic> json) {
    statusCode = json['statusCode'];
    success = json['success'];
    messages = List.castFrom<dynamic, dynamic>(json['messages']);
    data = List.from(json['data']).map((e) => Data.fromJson(e)).toList();
  }

  Map<String, dynamic> toJson() {
    final _data = <String, dynamic>{};
    _data['statusCode'] = statusCode;
    _data['success'] = success;
    _data['messages'] = messages;
    _data['data'] = data.map((e) => e.toJson()).toList();
    return _data;
  }
}

class Data {
  Data({
    required this.id,
    required this.title,
    required this.filename,
    required this.mimetype,
    required this.directcalling,
    this.parentid,
    required this.subcat,
  });
  late final int id;
  late final String title;
  late final String filename;
  late final String mimetype;
  late final int directcalling;
  late final Null parentid;
  late final List<Subcat> subcat;

  Data.fromJson(Map<String, dynamic> json) {
    id = json['id'];
    title = json['title'];
    filename = json['filename'];
    mimetype = json['mimetype'];
    directcalling = json['directcalling'];
    parentid = null;
    subcat = List.from(json['subcat']).map((e) => Subcat.fromJson(e)).toList();
  }

  Map<String, dynamic> toJson() {
    final _data = <String, dynamic>{};
    _data['id'] = id;
    _data['title'] = title;
    _data['filename'] = filename;
    _data['mimetype'] = mimetype;
    _data['directcalling'] = directcalling;
    _data['parentid'] = parentid;
    _data['subcat'] = subcat.map((e) => e.toJson()).toList();
    return _data;
  }
}

class Subcat {
  Subcat({
    required this.id,
    required this.title,
    required this.filename,
    required this.mimetype,
    required this.directcalling,
    required this.parentid,
    required this.subcat,
  });
  late final int id;
  late final String title;
  late final String filename;
  late final String mimetype;
  late final int directcalling;
  late final int parentid;
  late final List<dynamic> subcat;

  Subcat.fromJson(Map<String, dynamic> json) {
    id = json['id'];
    title = json['title'];
    filename = json['filename'];
    mimetype = json['mimetype'];
    directcalling = json['directcalling'];
    parentid = json['parentid'];
    subcat = List.castFrom<dynamic, dynamic>(json['subcat']);
  }

  Map<String, dynamic> toJson() {
    final _data = <String, dynamic>{};
    _data['id'] = id;
    _data['title'] = title;
    _data['filename'] = filename;
    _data['mimetype'] = mimetype;
    _data['directcalling'] = directcalling;
    _data['parentid'] = parentid;
    _data['subcat'] = subcat;
    return _data;
  }
}