how to access properties of json object flutter-CodePudding

I want to access the properties of this json object and display them for test purposes on the screen.

I can display the whole json object on the screen:

{
  "2021": {
            "januari": {
                "value": 100,
            },
            "februari": {
                "value": 200,
            },
        }
"2022": {
            "januari": {
                "value": 100,
            },
            "februari": {
                "value": 200,
            },
        }
}

This is how i display it:

 Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: const Text('Page View'),
        ),
        body: Container(
            child: Card(
                child: FutureBuilder(
          future: getJson(),
          builder: (BuildContext context, AsyncSnapshot<dynamic> snapshot) {
            if (snapshot.hasData) {
              return Text(snapshot.data);
            }
            return const Text("no data");
          },
        ))));
  }

It displays the json exactly like i showed with the example. I just wonder how i can access and show the properties for example "2021", "januari" and the value of "value" on the screen?

Edit

When i do: Text(snapshot.data['2021']['januari'])

i get: type 'String' is not a subtype of type 'int' of 'index'

CodePudding user response：

Here is sample for you. You can take it in dartpad. So to fix you behavior probably take your snapshot data and put it inside Map<dynamic,dynamic> and then use it like in code below.

import 'dart:convert';

String data = '''{
  "2021": {
    "januari": {
      "value": 100
    },
    "februari": {
      "value": 200
    }
  },
  "2022": {
    "januari": {
      "value": 100
    },
    "februari": {
      "value": 200
    }
  }
} ''';

void main() { 

  Map<dynamic,dynamic> json = jsonDecode(data);
  print(json.keys.first);
  print(json['2021'].keys.first);
  print(json['2021']['januari']['value']);
}