user8107351
Reputation: 427
How Do I convert this Complex Json to Dart Object
I have this complex (to me) json object, that I'd like to convert to a dart model, but I keep getting one error or the other.
It's a list of json objects like this:
{
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {
"name": "Congo",
"pop_est": 4012809,
"gdp_md_est": 15350,
"economy": "6. Developing region",
"income_grp": "4. Lower middle income",
"iso_a2": "CG",
"iso_a3": "COG",
"continent": "Africa",
"latitude": "-4.2634",
"longitude": "15.2832",
"confirmed": 143,
"deaths": 6,
"active": 126,
"recovered": 11
},
"geometry": {
"type": "Polygon",
"coordinates": [
[
[
12.995517205465177,
-4.781103203961884
],
[
12.620759718484491,
-4.438023369976136
],
[
12.318607618873926,
-4.606230157086188
],
[
11.91496300624209,
-5.037986748884791
],
[
11.093772820691925,
-3.978826592630547
],
[
11.855121697648114,
-3.426870619321051
],
[
11.478038771214303,
-2.765618991714241
],
[
11.820963575903193,
-2.514161472181982
],
[
12.495702752338161,
-2.391688327650243
],
[
12.575284458067642,
-1.948511244315135
],
[
13.109618767965628,
-2.428740329603514
],
[
13.99240726080771,
-2.4708049454891
],
[
14.299210239324564,
-1.998275648612214
],
[
14.425455763413593,
-1.333406670744971
],
[
14.316418491277743,
-0.552627455247048
],
[
13.843320753645655,
0.038757635901149
],
[
14.276265903386957,
1.196929836426619
],
[
14.026668735417218,
1.395677395021153
],
[
13.282631463278818,
1.31418366129688
],
[
13.003113641012078,
1.83089630778332
],
[
13.075822381246752,
2.267097072759015
],
[
14.33781253424658,
2.227874660649491
],
[
15.146341993885244,
1.964014797367184
],
[
15.940918816805064,
1.727672634280295
],
[
16.012852410555354,
2.267639675298085
],
[
16.537058139724135,
3.198254706226279
],
[
17.133042433346304,
3.728196519379452
],
[
17.809900343505262,
3.56019643799857
],
[
18.45306521980993,
3.504385891123349
],
[
18.39379235197114,
2.90044342692822
],
[
18.094275750407434,
2.365721543788055
],
[
17.898835483479587,
1.741831976728278
],
[
17.774191928791566,
0.855658677571085
],
[
17.826540154703252,
0.288923244626105
],
[
17.66355268725468,
-0.058083998213817
],
[
17.638644646889986,
-0.424831638189247
],
[
17.523716261472856,
-0.743830254726987
],
[
16.865306837642123,
-1.225816338713287
],
[
16.407091912510054,
-1.740927015798682
],
[
15.972803175529151,
-2.712392266453612
],
[
16.0062895036543,
-3.535132744972529
],
[
15.75354007331475,
-3.855164890156096
],
[
15.170991652088444,
-4.343507175314301
],
[
14.58260379401318,
-4.97023894615014
],
[
14.209034864975223,
-4.793092136253598
],
[
14.144956088933299,
-4.510008640158715
],
[
13.600234816144678,
-4.50013844159097
],
[
13.258240187237048,
-4.882957452009165
],
[
12.995517205465177,
-4.781103203961884
]
]
]
}
},
{
"type": "Feature",
"properties": {
"name": "Angola",
"pop_est": 12799293,
"gdp_md_est": 110300,
"economy": "7. Least developed region",
"income_grp": "3. Upper middle income",
"iso_a2": "AO",
"iso_a3": "AGO",
"continent": "Africa",
"latitude": "-11.2027",
"longitude": "17.8739",
"confirmed": 24,
"deaths": 2,
"active": 16,
"recovered": 6
},
"geometry": {
"type": "MultiPolygon",
"coordinates": [
[
[
[
16.326528354567046,
-5.877470391466218
],
[
16.57317996589614,
-6.622644545115094
],
[
16.86019087084523,
-7.222297865429979
],
[
17.08999596524717,
-7.545688978712476
],
[
17.472970004962292,
-8.068551120641656
],
[
18.13422163256905,
-7.987677504104866
],
[
18.464175652752687,
-7.847014255406477
],
[
19.01675174324967,
-7.98824594486014
],
[
19.166613396896082,
-7.738183688999725
],
[
19.417502475673217,
-7.155428562044278
],
[
20.037723016040218,
-7.11636117923166
],
[
20.09162153492062,
-6.943090101756951
],
[
20.601822950938327,
-6.939317722199689
],
[
20.51474816252653,
-7.299605808138665
],
[
21.728110792739756,
-7.290872491081316
],
[
21.746455926203367,
-7.920084730667114
],
[
21.94913089365204,
-8.305900974158305
],
[
21.801801385187957,
-8.908706556842986
],
[
21.875181919042404,
-9.523707777548566
],
[
22.208753289486424,
-9.89479623783653
],
[
22.155268182064333,
-11.084801120653779
],
[
22.402798292742432,
-10.99307545333569
],
[
22.83734541188477,
-11.017621758674338
],
[
23.456790805767465,
-10.867863457892483
],
[
23.912215203555746,
-10.926826267137542
],
[
24.017893507592614,
-11.237298272347118
],
[
23.90415368011824,
-11.722281589406336
],
[
24.079905226342902,
-12.191296888887308
],
[
23.930922072045377,
-12.565847670138822
],
[
24.016136508894704,
-12.911046237848552
],
[
21.933886346125945,
-12.898437188369357
],
[
21.887842644953878,
-16.080310153876894
],
[
22.56247846852429,
-16.898451429921835
],
[
23.215048455506093,
-17.523116143465952
],
[
21.377176141045595,
-17.93063648851971
],
[
18.95618696460363,
-17.789094740472237
],
[
18.26330936043422,
-17.309950860262006
],
[
14.209706658595051,
-17.353100681225712
],
[
14.058501417709039,
-17.423380629142656
],
[
13.462362094789967,
-16.97121184658874
],
[
12.814081251688407,
-16.941342868724078
],
[
12.215461460019384,
-17.111668389558062
],
[
11.734198846085148,
-17.3018893368245
],
[
11.64009606288161,
-16.67314218512921
],
[
11.778537224991567,
-15.79381601325069
],
[
12.123580763404448,
-14.878316338767931
],
[
12.175618930722266,
-14.449143568583892
],
[
12.500095249083017,
-13.547699883684402
],
[
12.738478631245442,
-13.137905775609935
],
[
13.312913852601838,
-12.483630466362513
],
[
13.633721144269828,
-12.038644707897191
],
[
13.738727654686926,
-11.297863050993143
],
[
13.686379428775297,
-10.731075941615842
],
[
13.38732791510216,
-10.373578383020728
],
[
13.120987583069875,
-9.766897067914115
],
[
12.875369500386569,
-9.166933689005488
],
[
12.929061313537801,
-8.959091078327575
],
[
13.236432732809874,
-8.562629489784342
],
[
12.933040398824316,
-7.596538588087753
],
[
12.72829837408392,
-6.927122084178805
],
[
12.227347039446443,
-6.294447523629372
],
[
12.322431674863566,
-6.100092461779653
],
[
12.735171339578699,
-5.965682061388478
],
[
13.02486941900699,
-5.984388929878108
],
[
13.375597364971895,
-5.864241224799557
],
[
16.326528354567046,
-5.877470391466218
]
]
],
[
[
[
12.436688266660923,
-5.684303887559224
],
[
12.18233686692028,
-5.789930515163803
],
[
11.914963006242116,
-5.037986748884734
],
[
12.318607618873926,
-4.606230157086158
],
[
12.62075971848455,
-4.438023369976121
],
[
12.995517205465205,
-4.781103203961919
],
[
12.631611769265845,
-4.991271254092936
],
[
12.468004184629763,
-5.248361504744992
],
[
12.436688266660923,
-5.684303887559224
]
]
]
]
}
}
] //Missing bracket
}
But I only need this part:
"properties": {
"name": "Angola",
"pop_est": 12799293,
"gdp_md_est": 110300,
"economy": "7. Least developed region",
"income_grp": "3. Upper middle income",
"iso_a2": "AO",
"iso_a3": "AGO",
"continent": "Africa",
"latitude": "-11.2027",
"longitude": "17.8739",
"confirmed": 24,
"deaths": 2,
"active": 16,
"recovered": 6
},
I tried creating a model just for the part I need above like so:
class AfricaData {
Properties properties;
AfricaData({this.properties});
AfricaData.fromJson(Map<String, dynamic> json) {
properties = json['properties'] != null
? new Properties.fromJson(json['properties'])
: null;
}
Map<String, dynamic> toJson() {
final Map<String, dynamic> data = new Map<String, dynamic>();
if (this.properties != null) {
data['properties'] = this.properties.toJson();
}
return data;
}
}
class Properties {
String name;
int popEst;
int gdpMdEst;
String economy;
String incomeGrp;
String isoA2;
String isoA3;
String continent;
String latitude;
String longitude;
int confirmed;
int deaths;
int active;
int recovered;
Properties(
{this.name,
this.popEst,
this.gdpMdEst,
this.economy,
this.incomeGrp,
this.isoA2,
this.isoA3,
this.continent,
this.latitude,
this.longitude,
this.confirmed,
this.deaths,
this.active,
this.recovered});
Properties.fromJson(Map<String, dynamic> json) {
name = json['name'];
popEst = json['pop_est'];
gdpMdEst = json['gdp_md_est'];
economy = json['economy'];
incomeGrp = json['income_grp'];
isoA2 = json['iso_a2'];
isoA3 = json['iso_a3'];
continent = json['continent'];
latitude = json['latitude'];
longitude = json['longitude'];
confirmed = json['confirmed'];
deaths = json['deaths'];
active = json['active'];
recovered = json['recovered'];
}
Map<String, dynamic> toJson() {
final Map<String, dynamic> data = new Map<String, dynamic>();
data['name'] = this.name;
data['pop_est'] = this.popEst;
data['gdp_md_est'] = this.gdpMdEst;
data['economy'] = this.economy;
data['income_grp'] = this.incomeGrp;
data['iso_a2'] = this.isoA2;
data['iso_a3'] = this.isoA3;
data['continent'] = this.continent;
data['latitude'] = this.latitude;
data['longitude'] = this.longitude;
data['confirmed'] = this.confirmed;
data['deaths'] = this.deaths;
data['active'] = this.active;
data['recovered'] = this.recovered;
return data;
}
}
So far I've tried the following:
1)
var data = json.decode(response.body);
var dataModel = (data[1]['features'][0]['properties'] as List).map((f) => AfricaData.fromJson(f)).toList();
2)
Map<String, dynamic> data = json.decode(response.body);
var dataModel = (data['type']['features']['type']['properties'] as List).map((f) => AfricaData.fromJson(f)).toList();
But I keep getting different errors, particularly InternalLinkedHashMap' is not a subtype of type 'List' in type cast
Upvotes: 0
Views: 106
Answers (1)
F Perroch
Reputation: 2225
To help you, you can use converters from json to Dart such as
You just have to past your json and copy the result of dart objects generated for you.
Once it's done, you can get your properties values as a List like this :
var obj = MyObject.fromJson(json.decode(str));
print(obj.features[0].properties.toJson().values.toList());
Upvotes: 1
Related Questions
- convert JSON to array -flutter
- how to parse dynamic complex json to dart object or model
- Converting complex JSON string to Map
- from json to object dart
- convert json to dart
- Dart convert array of json objects to list of objects
- How to convert json to dart when json is a list of arrays?
- How to convert inner json part into object in dart/flutter
- JSON Array to JSON Object
- How to convert a nested JSON into an Object