_TypeError (type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'Iterable<dynamic>') Flutter

Question

while fetching single user from api i got above error mentioned in title my response is

{"success":true,"data":{"id":4,"user_id":"4","email":"[email protected]","secondaryPhone":"[phone]"},"message":"User retrieved successfully."}

My model class

class UsersModel({this.id, this.user_id, this.email, this.secondaryPhone});

My api call is as follows

class UsersApi {
  Future<List<UsersModel>> fetchUsersById(String uId) async 
 {String singleUser = CallApi.url+CallApi.sinleUser+uId; 
   
 Map<String,String> headers =  
  { 'Accept' : 'application/json'};  
  var response = await http.get(singleUser ,headers:headers);  
       List<UsersModel> users= List<UsersModel>();
    if(response.statusCode == 200){
      var jsonData = jsonDecode(response.body);
      var data = jsonData["data"];
      for( var userr in data ) // error comes on this line
{        
UsersModel user = UsersModel(
id:item["id"].toString(),
user_id:item["user_id"].toString(),
email:item["email"].toString(),
secondaryPhone:item["secondaryPhone"].toString(),
);
 users.add(user);
      }
}
  return users;
}


}

any help is apprciated.

Answer 1

The JSON you show doesn't contain any lists. You imply that when you fetch multiple users, this code works fine, likely because jsonData["data"] is actually returning a List when you fetch multiple.

To solve this, you should do a check of the type that jsonData["data"] is. If it's a List then do what you currently have, if not then, you process it differently.

Ex.

Future<List<UsersModel>> fetchUsersById(String uId) async {
  String singleUser = CallApi.url+CallApi.sinleUser+uId;
   
 Map<String,String> headers =  
  { 'Accept' : 'application/json'};  
  var response = await http.get(singleUser ,headers:headers);  
       List<UsersModel> users= List<UsersModel>();
    if(response.statusCode == 200){
      var jsonData = jsonDecode(response.body);
      var data = jsonData["data"];

      //Handle data differently if it's a Map
      if(data is Map) {
        UsersModel user = UsersModel(
          id:item["id"].toString(),
          user_id:item["user_id"].toString(),
          email:item["email"].toString(),
          secondaryPhone:item["secondaryPhone"].toString(),
        );
        users.add(user);
        return users;
      }

      //Otherwise, do what you currently have
      for( var userr in data )
      {        
        UsersModel user = UsersModel(
          id:item["id"].toString(),
          user_id:item["user_id"].toString(),
          email:item["email"].toString(),
          secondaryPhone:item["secondaryPhone"].toString(),
        );
        users.add(user);
      }
  }
  return users;
}