unable to retrieve object inside object - flutter

Question

I am new to flutter . i am trying to fetch responnse from api . i am getting response as 200 but unable to retreive particular object inside it .
please have a look at a model class below and suggest me what wrong i am doing
class Response {
bool success;
List<dynamic> errors;
List<CourseParent> courses;
Batches coursedetail;
Response({this.success,this.errors,this.courses,this.coursedetail});
factory Response.fromJson(Map<String, dynamic> map) {
return Response(
errors: map['errors'],
success: map['success'],
courses: map['courses'] != null
? map['courses'].map<CourseParent>((json) => CourseParent.fromJson(json)).toList()
: null,
coursedetail: map['courseDetails'] != null
? map['courseDetails'].map<Batches>((json) => Batches.fromJson(json))
: null,
);
}
Map<String, dynamic> toJson() {
return {"success": success, "errors": errors, "courses": courses, "courseDetails" : coursedetail};
}
#override
String toString() {
return 'Response{ success: $success, errors: $errors , courses: $courses, courseDetails: $coursedetail }';
}
}
List<Response> profileFromJson(String jsonData) {
final data = json.decode(jsonData);
return List<Response>.from(data.map((item) => Response.fromJson(item)));
}
Response responseFromJson(String str) {
final jsonData = json.decode(str);
print("##-response"+jsonData.toString());
return Response.fromJson(jsonData);
}
String responseToJson(Response data) {
final jsonData = data.toJson();
print("##--encoding"+json.encode(jsonData));
return json.encode(jsonData);
}
i am getting the error as below
NoSuchMethodError: Class '_InternalLinkedHashMap<String, dynamic>' has no instance method 'map' with matching arguments.
Acutall expected json is below
{
"success": true,
"courseDetails": {
"courseId": 34,
"title": "Taxi Drivers Qualification Program",
"code": "TX001",
"image": "uploads\\9e5dba0e-0e25-4247-a3fa-a2a404aadacd.jpg",
"target": 0,
"batches": [
{
"batchId": 41,
"courseId": 34,
"instructorId": 22,
"venueId": 1,
"startDate": "2021-01-03T00:00:00",
"endDate": "2021-01-17T00:00:00",
"startTime": "2021-01-03T09:17:00",
"endTime": "2021-01-03T12:17:00",
"capacity": 25,
"gender": 2,
"instructor": [
{
"instructorId": 22,
"civilId": "931285",
"forceId": "123",
"title": 15,
"fullname": "Mansoor Abdulrahim Al Rasbi",
"email": "steve.jobs#apple.com",
"mobile": "99699633",
"type": 1
}
],
"venue": [
{
"venueId": 1,
"name": "B22",
"branchId": 1,
"branch": [
{
"branchId": 1,
"name": "Head Quarters - Muscat",
"capacityTheoretical": 175,
"capacityPractical": 125
}
],
"bookingFees": 25
},
{
"venueId": 21,
"name": "Meetings Hall",
"branchId": 1,
"branch": [
{
"branchId": 1,
"name": "Head Quarters - Muscat",
"capacityTheoretical": 175,
"capacityPractical": 125
}
],
"bookingFees": 20
},
{
"venueId": 41,
"name": "Store Muscat Branch",
"branchId": 1,
"branch": [
{
"branchId": 1,
"name": "Head Quarters - Muscat",
"capacityTheoretical": 175,
"capacityPractical": 125
}
]
}
]
}
]
}
}

Answer 1

You need to parse courseDetails directly, it is an object, not Map or List:
coursedetail: map['courseDetails'] != null ? Batches.fromJson(map['courseDetails']) : null;