how to get value from the List of Map?-CodePudding

How to get "plate" value in such object? Also how can I get value inside 'fixation', because it is list?

[
  {
    "id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
    "car": {
      "id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
      "plate": "string",
      "fixations": [
        "string"
      ]
    },
    "fixed": "2022-08-17T09:55:33.709Z",
    "speed": 0,
    "latitude": 0,
    "longitude": 0,
    "upload": true,
    "image": {
      "id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
      "file": "string"
    }
  }
]

I write code like this:

 body: FutureBuilder<List>(
        future: AllFixation().fetchAllFixation(),
        builder: (context, snapshot) {
          return ListView.builder(
              itemCount: snapshot.data?.length ?? 0,
              itemBuilder: (context, index) {
                return Text(snapshot.data?[index]["upload"].toString() ?? '');
              });
        },
      ),

CodePudding user response：

For this situation, you should write a class that implements a .fromMap() method to comfortable handle data. But, if your want to use a "raw" data, you should be carefull with such constructions. In your case, you can get "plate" value like this:

snapshot.data?[index]["car"]["plate"] as String;

To get fixation, you should follow this snippet:

var myList = snapshot.data?[index]["car"]["fixations"].cast<String>();

Then, you could work with myList as usual List<String>.

I used .cast<String>() instead of as List<String>, because in some situations, "as List<String>" will throw Exception like "List<String> is not subtype of List<dynamic>"