Flutter：从嵌套的 json null 中获取数据

Question

I have this JSON data from an API:

[
  {
    "date": "2021-02-10",
    "matches": [
      {
        "id": 1,
        "home": "Turkey",
        "away": "Italy",
        "h_goals": 0,
        "a_goals": 0,
        "predect": [
          {
            "id": 3,
            "user_id": 10,
            "match_id": 1,
            "h_predect": 1,
            "a_predect": 1,
            "point": 0,
          }
        ]
      },
]

I made service to get data without model and create some condition:

Future userPredects(username, token) async {
    try {
      List dataList = [];

      var response = await http.get(url + 'matches/$username', headers: {
        'Content-Type': 'application/json',
        'Accept': 'application/json',
        'Authorization': 'Bearer $token',
      });
      var data = jsonDecode(response.body);

      for (var item in data) {
        var count = 0;
        for (var match in item['matches']) {
          count = count + match['predect'].length;
        }
        if (count > 0) {
          dataList.add(item);
        }
      }
      return dataList;
    } catch (e) {
      print(e);
    }
  }

I used it in future builder and get all data just those inside predect object:

How can I solve it?

Edit: with more detail,adding future builder widget

return FutureBuilder(
            future: mathesProv.userPredects(username, token),
            builder: (context, snapshot) {
              if (snapshot.hasData) {
                return ListView.builder(
                    itemCount: snapshot.data.length,
                    itemBuilder: (context, index) {
                      var item = snapshot.data[index];
                      return Card(
                        margin: EdgeInsets.only(top: 10, bottom: 10),
                        child: Column(
                          children: [
                            Text('${item['date']}'),
                            for (var i = 0; i < item['matches'].length; i++)
                               child: Row(
                                   children: [
                                     Text('${item['matches'][i]['home']}'),
                                     Text('${item['matches'][i]['predect'][0]['h_predect']}'),

the problem is item['matches'][i]['home'] get data correctly but item['matches'][i]['predect'][0]['h_predect'] get null

Answer 1

Your API returns JsonArray not JsonObject so that is List not Map .

To get first element use first index:

item[0]['matches'][i]['home']
item[0]['matches'][i]['predect'][0]['h_predect']