How to Deserialize a list of objects from json in flutter Ask Question

Question

I am using the dart package json_serializable for json serialization. Looking at the flutter documentation it shows how to deserialize a single object as follow:

Future<Post> fetchPost() async {
  final response =
  await http.get('https://jsonplaceholder.typicode.com/posts/1');

  if (response.statusCode == 200) {
  // If the call to the server was successful, parse the JSON
  return Post.fromJson(json.decode(response.body));
  } else {
    // If that call was not successful, throw an error.
    throw Exception('Failed to load post');
  }
}

However, I am not familiar enough with dart to figure out how to do the same for a list of items instead of a single instance.

Answer 1

To deserialize a list of objects from JSON in Flutter:

1. Create a model class for your object and annotate it with @JsonSerializable().
2. Add the necessary dependencies to your pubspec.yaml file.
3. Generate the JSON serialization code by running flutter pub run build_runner build.
4. Use http package to fetch the JSON data, and then use json.decode() and List.map() to convert the list of maps to a list of objects.

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