NoSuchMethodError: The method 'map' was called on null

[Mounika Sivanaga]

Hi , I am getting response but unable to parse to list. 

Can you please give an example to parse into list with nested arrays in json.

This is my code.

if(res.statusCode == 200){
  print(mediaResponse);
  if(mediaResponse.status == 1){
  final imageModel = json.decode(res.body);
  print('iamgemodel response $imageModel');
  var imageData = imageModel["data"] as List;
  for(var model in imageData){
    setState(() {
      images.add(new ImageModel.fromJson(model));
    });
  }
  print("List Size: ${images.length}");
  }
}

Model class:

import 'dart:convert';

ImageModel imageModelFromJson(String str) {
  final jsonData = json.decode(str);
  return ImageModel.fromJson(jsonData);
}

String imageModelToJson(ImageModel data) {
  final dyn = data.toJson();
  return json.encode(dyn);
}

class ImageModel {
  int status;
  List<Datum> data;
  int totalRecord;

  ImageModel({
    this.status,
    this.data,
    this.totalRecord,
  });


  factory ImageModel.fromJson(Map<String, dynamic> json) => new ImageModel(
    status: json["status"],
    data: new List<Datum>.from(json["data"].map((x) => Datum.fromJson(x))),
    totalRecord: json["totalRecord"],
  );

  Map<String, dynamic> toJson() => {
    "status": status,
    "data": new List<dynamic>.from(data.map((x) => x.toJson())),
    "totalRecord": totalRecord,
  };

  @override
  String toString() {
    // TODO: implement toString
    return '$status $data $totalRecord';
  }
}

class Datum {
  String id;
  String name;
  String thumbnailUrl;
  int plays;
  String categories;
  String categoriesIds;
  String dataUrl;
  int duration;
  String createdAt;
  int status;
  int statusc;
  int mediaType;

  Datum({
    this.id,
    this.name,
    this.thumbnailUrl,
    this.plays,
    this.categories,
    this.categoriesIds,
    this.dataUrl,
    this.duration,
    this.createdAt,
    this.status,
    this.statusc,
    this.mediaType,
  });

  factory Datum.fromJson(Map<String, dynamic> json) => new Datum(
    id: json["id"] == null ? null : json["id"],
    name: json["name"] == null ? null : json["name"],
    thumbnailUrl: json["thumbnailUrl"] == null ? null : json["thumbnailUrl"],
    plays: json["plays"] == null ? null : json["plays"],
    categories: json["categories"] == null ? null : json["categories"],
    categoriesIds: json["categoriesIds"] == null ? null : json["categoriesIds"],
    dataUrl: json["dataUrl"] == null ? null : json["dataUrl"],
    duration: json["duration"] == null ? null : json["duration"],
    createdAt: json["createdAt"] == null ? null : json["createdAt"],
    status: json["status"] == null ? null : json["status"],
    statusc: json["statusc"] == null ? null : json["statusc"],
    mediaType: json["mediaType"] == null ? null : json["mediaType"],
  );

  Map<String, dynamic> toJson() => {
    "id": id == null ? null : id,
    "name": name == null ? null : name,
    "thumbnailUrl": thumbnailUrl == null ? null : thumbnailUrl,
    "plays": plays == null ? null : plays,
    "categories": categories == null ? null : categories,
    "categoriesIds": categoriesIds == null ? null : categoriesIds,
    "dataUrl": dataUrl == null ? null : dataUrl,
    "duration": duration == null ? null : duration,
    "createdAt": createdAt == null ? null : createdAt,
    "status": status == null ? null : status,
    "statusc": statusc == null ? null : statusc,
    "mediaType": mediaType == null ? null : mediaType,
  };

  @override
  String toString() {
    // TODO: implement toString
    return '$id $name $thumbnailUrl $plays $categories $categoriesIds $dataUrl $duration';
  }
}


JSON Response:

{
    "status": 1,
    "data": [
        {
            "id": "0_314t2peg",
            "name": "Countdown",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_314t2peg/version/100002",
            "plays": 12,
            "categories": "News>BBC,News>CNBC,News>PublicTV,News>TV9,Shows>Thriller,Shows>Regional",
            "categoriesIds": "19,20,18,17,13,16",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_314t2peg/format/url/protocol/http",
            "duration": 13,
            "createdAt": "28/11/18 11:26:39",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_joyzmp2z",
            "name": "voice 4k",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_joyzmp2z/version/100002",
            "plays": 14,
            "categories": "News>BBC,News>CNBC,News>PublicTV,News>TV9,Shows>Thriller,Shows>Regional",
            "categoriesIds": "19,20,18,17,13,16",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_joyzmp2z/format/url/protocol/http",
            "duration": 20,
            "createdAt": "28/11/18 11:25:56",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_yndwskxv",
            "name": "news",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_yndwskxv/version/100012",
            "plays": 6,
            "categories": "News>BBC,News>TV9,Shows>Regional",
            "categoriesIds": "19,17,16",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_yndwskxv/format/url/protocol/http",
            "duration": 17,
            "createdAt": "28/11/18 11:24:12",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_jd7hul0b",
            "name": "GB10Sec",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_jd7hul0b/version/100002",
            "plays": 8,
            "categories": "Shows>Thriller,Shows>Action,Shows>Sci-Fi",
            "categoriesIds": "13,15,14",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_jd7hul0b/format/url/protocol/http",
            "duration": 10,
            "createdAt": "28/11/18 11:14:40",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_bz9qlkle",
            "name": "Thugs Of Hindostan",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_bz9qlkle/version/100002",
            "plays": 0,
            "categories": null,
            "categoriesIds": null,
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_bz9qlkle/format/url/protocol/http",
            "duration": 218,
            "createdAt": "28/11/18 11:08:45",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_swm5unow",
            "name": "Shivaay",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_swm5unow/version/100002",
            "plays": 0,
            "categories": null,
            "categoriesIds": null,
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_swm5unow/format/url/protocol/http",
            "duration": 230,
            "createdAt": "28/11/18 11:08:23",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_1n1qg0hq",
            "name": "Rocky Handsome",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_1n1qg0hq/version/100012",
            "plays": 9,
            "categories": "Movies>Drama,Movies>Sci-Fi",
            "categoriesIds": "22,24",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_1n1qg0hq/format/url/protocol/http",
            "duration": 184,
            "createdAt": "28/11/18 11:08:03",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_3vk4o4ie",
            "name": "Genius",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_3vk4o4ie/version/100012",
            "plays": 5,
            "categories": "Movies>Drama,Movies>Sci-Fi",
            "categoriesIds": "22,24",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_3vk4o4ie/format/url/protocol/http",
            "duration": 200,
            "createdAt": "28/11/18 11:07:46",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_jb8en5kn",
            "name": "Commando",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_jb8en5kn/version/100012",
            "plays": 2,
            "categories": "Movies>Thriller,Movies>Drama,Movies>Sci-Fi",
            "categoriesIds": "23,22,24",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_jb8en5kn/format/url/protocol/http",
            "duration": 162,
            "createdAt": "28/11/18 11:07:25",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_es5vzzca",
            "name": "Action Jackson",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_es5vzzca/version/100002",
            "plays": 0,
            "categories": "Movies>Thriller,Movies>Drama,Movies>Sci-Fi",
            "categoriesIds": "23,22,24",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_es5vzzca/format/url/protocol/http",
            "duration": 175,
            "createdAt": "28/11/18 11:06:13",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_2tfugvsm",
            "name": "jellyfish-25-mbps-hd-hevc",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_2tfugvsm/version/100002",
            "plays": 0,
            "categories": null,
            "categoriesIds": null,
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_2tfugvsm/format/url/protocol/http",
            "duration": 30,
            "createdAt": "22/11/18 09:05:26",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_z5i5fmiw",
            "name": "small (3)",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_z5i5fmiw/version/100022",
            "plays": 1,
            "categories": null,
            "categoriesIds": null,
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_z5i5fmiw/format/url/protocol/http",
            "duration": 6,
            "createdAt": "22/11/18 06:41:15",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_0i4hbs9o",
            "name": "dolbycanyon",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_0i4hbs9o/version/100012",
            "plays": 1,
            "categories": null,
            "categoriesIds": null,
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_0i4hbs9o/format/url/protocol/http",
            "duration": 38,
            "createdAt": "22/11/18 06:38:13",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_wbd3wu38",
            "name": "Mary and little lamb",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_wbd3wu38/version/100002",
            "plays": 3,
            "categories": "Shows>Sci-Fi,Shows>Regional,Movies>Action",
            "categoriesIds": "14,16,21",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_wbd3wu38/format/url/protocol/http",
            "duration": 184,
            "createdAt": "12/11/18 10:36:17",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_k4unuqi2",
            "name": "Johny Johny",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_k4unuqi2/version/100002",
            "plays": 2,
            "categories": "Shows>Sci-Fi,Movies>Action",
            "categoriesIds": "14,21",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_k4unuqi2/format/url/protocol/http",
            "duration": 186,
            "createdAt": "12/11/18 10:36:17",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_3w4xjt5x",
            "name": "One Little Flower",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_3w4xjt5x/version/100012",
            "plays": 7,
            "categories": "TV>Entertainment",
            "categoriesIds": "25",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_3w4xjt5x/format/url/protocol/http",
            "duration": 83,
            "createdAt": "12/11/18 10:20:14",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_w64yjfen",
            "name": "I'm A Little Teapot",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_w64yjfen/version/100012",
            "plays": 9,
            "categories": "Shows>Action,TV>Shows",
            "categoriesIds": "15,11",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_w64yjfen/format/url/protocol/http",
            "duration": 104,
            "createdAt": "12/11/18 10:20:14",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_591qnfyf",
            "name": "Little Jack Horner",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_591qnfyf/version/100002",
            "plays": 93,
            "categories": "Shows>Regional,Movies>Action,TV>Shows",
            "categoriesIds": "16,21,11",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_591qnfyf/format/url/protocol/http",
            "duration": 87,
            "createdAt": "12/11/18 10:18:49",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_n1wvco0o",
            "name": "My School",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_n1wvco0o/version/100012",
            "plays": 21,
            "categories": "TV>Shows",
            "categoriesIds": "11",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_n1wvco0o/format/url/protocol/http",
            "duration": 75,
            "createdAt": "12/11/18 10:18:49",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_srtxu635",
            "name": "Hop a little",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_srtxu635/version/100012",
            "plays": 24,
            "categories": "Movies>Thriller,Movies>Action,TV>Shows",
            "categoriesIds": "23,21,11",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_srtxu635/format/url/protocol/http",
            "duration": 108,
            "createdAt": "12/11/18 10:18:49",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_uuu7jii2",
            "name": "Come Little Children",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_uuu7jii2/version/100002",
            "plays": 4,
            "categories": "Movies>Sci-Fi,Movies>Action,TV>Shows",
            "categoriesIds": "24,21,11",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_uuu7jii2/format/url/protocol/http",
            "duration": 94,
            "createdAt": "12/11/18 10:16:00",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_9ld6kzph",
            "name": "story telling",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_9ld6kzph/version/100002",
            "plays": 2,
            "categories": "Movies>Drama,Movies>Action",
            "categoriesIds": "22,21",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_9ld6kzph/format/url/protocol/http",
            "duration": 73,
            "createdAt": "12/11/18 10:16:00",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_cz6egmc9",
            "name": "Tenali Raman In English",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_cz6egmc9/version/100002",
            "plays": 1,
            "categories": "Movies>Action,Shows>Thriller",
            "categoriesIds": "21,13",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_cz6egmc9/format/url/protocol/http",
            "duration": 151,
            "createdAt": "12/11/18 10:16:00",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_pj8ansdd",
            "name": "The two frogs",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_pj8ansdd/version/100002",
            "plays": 1,
            "categories": "News>TV9,Movies>Action",
            "categoriesIds": "17,21",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_pj8ansdd/format/url/protocol/http",
            "duration": 141,
            "createdAt": "12/11/18 10:16:00",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_7wy5icdl",
            "name": "Twinkle Twinkle",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_7wy5icdl/version/100002",
            "plays": 1,
            "categories": "News>CNBC",
            "categoriesIds": "20",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_7wy5icdl/format/url/protocol/http",
            "duration": 181,
            "createdAt": "12/11/18 10:16:00",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_0l7xkwee",
            "name": "Two little hands",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_0l7xkwee/version/100002",
            "plays": 5,
            "categories": "Movies>Action,News>BBC",
            "categoriesIds": "21,19",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_0l7xkwee/format/url/protocol/http",
            "duration": 59,
            "createdAt": "12/11/18 10:16:00",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_58md9gkm",
            "name": "amazoneco",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_58md9gkm/version/100002",
            "plays": 0,
            "categories": "News>PublicTV",
            "categoriesIds": "18",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_58md9gkm/format/url/protocol/http",
            "duration": 36,
            "createdAt": "05/11/18 12:01:44",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_f90klu3n",
            "name": "arunicecream",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_f90klu3n/version/100012",
            "plays": 2,
            "categories": null,
            "categoriesIds": null,
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_f90klu3n/format/url/protocol/http",
            "duration": 15,
            "createdAt": "05/11/18 12:01:44",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_hmr8atha",
            "name": "bahubalitrailer",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_hmr8atha/version/100012",
            "plays": 11,
            "categories": "TV>Songs,Shows>Thriller,Shows>Regional",
            "categoriesIds": "12,13,16",
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_hmr8atha/format/url/protocol/http",
            "duration": 21,
            "createdAt": "05/11/18 12:01:44",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        },
        {
            "id": "0_kzwqw8eq",
            "name": "BigData",
            "thumbnailUrl": "http://onnet-video-platform/p/102/sp/10200/thumbnail/entry_id/0_kzwqw8eq/version/100012",
            "plays": 1,
            "categories": null,
            "categoriesIds": null,
            "dataUrl": "http://159.65.156.204/p/102/sp/10200/playManifest/entryId/0_kzwqw8eq/format/url/protocol/http",
            "duration": 93,
            "createdAt": "05/11/18 12:01:44",
            "status": 2,
            "statusc": 2,
            "mediaType": 1
        }
    ],
    "totalRecord": 30
}

[Bened]

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