type 'List<String>' is not a subtype of type 'String' in type cast

Question

I have this:

List<String> _filters = <String>[8, 11];

I pass this _filters into this endpoint:

this.api.setInterests(token, _filters)
  .then((res) {
    print(res);
  });

which looks like this:

  Future setInterests(String token, List<String> interests) {
    return _netUtil.post(BASE_URL + "/setinterests", body: {
      "token": token,
      "interests": interests
    }).then((dynamic res) {
      return res;
    });
  }

Passing _filters always throws the error:

type 'List<String>' is not a subtype of type 'String' in type cast

I don't know what else dart wants from me.

Answer 1

1. You need to add json.encode(data) in body
2. Add these two header
   'Content-type': 'application/json',
   'Accept': 'application/json',

3. Create map of your data

   final Map<String, dynamic> data = new Map<String, dynamic>();
    data['token'] = token;
    data['interests'] = interests;
   

4. Call api like this
   

   http.post(url,<br>
   body: json.encode(data),
   headers: { 'Content-type': 'application/json',
     'Accept': 'application/json'},
   encoding: encoding)
   .then((http.Response response) {
   
        // print(response.toString());
   
   }
   

Answer 2

I found the answer. I just added .toString() to the _filters List.

  this.api.setInterests(token, _filters.toString())
  .then((res) {
    print(res);
  });