How can i convert Future to User in my class?

Question

What i am trying to do is i am fetching profile from fetchUser.But i don't know any other way that i can pull http data other than string.

class FollowingUserModel {
  final String id;
  final String author;
  User profile;
  final String profileid;

  FollowingUserModel({this.id, this.profileid, this.author, this.profile}) {  profile = fetchUser() as User; }

  Future<User> fetchUser() async{
    final response = await http.get("$SERVER_IP/api/users/$profileid/?format=json");
    if (response.statusCode == 200) {
      var responseJson = json.decode(response.body);
      return User.fromJSON(responseJson);}}

  factory  FollowingUserModel.fromJSON(Map<String, dynamic> jsonMap) {
    return  FollowingUserModel(
      id: jsonMap['id'] as String,
      author:  jsonMap['author'] as String,
      profileid: jsonMap['profile'] as String,
);}}

Does anybody know how to do it?

not really.I don't know what to do as it has too much explanation there.It would be better if you break it down as an answer. @nvoigt — umarbeyoglu, Feb 10 '21 at 15:27
Well, the point of duplicates is that we do not want to have a single, hand-tailored answer for each variant of the same problem, as it makes it hard to find a solution, since each answer only applies to the exact question asked. Since your question is very broad, I don't know how to narrow down an answer. Do you have anything *specific* that you have problems with? Do you get compiler errors, runtime errors? — nvoigt, Feb 10 '21 at 15:31
I explained it up there,i will explain it again. I want to fetch my User from my class,but i don't know how to return it as a regular User. I want to assign the fetchUser() value to "profile" correctly,thats what i mean. — umarbeyoglu, Feb 10 '21 at 15:34
I don't know what to tell you. The two answers you got are correct, to wait for a Future to finish and get it's result, you need to use the `await` keyword as shown. If you want to know *why* you have to do that, you can follow my link above. If you have a problem with doing what the answers says, you need to either edit your question to be more specific about the problem you have with it, or ask a follow up question if you think it's too much for a single question. — nvoigt, Feb 10 '21 at 15:37
I get what you mean.The thing is that i tried both of them,but they still give errors for me. I call my functions from FollowingUserModel class,not inside state or so because it would be too hard for me instead of this one.Thanks for your help anyway — umarbeyoglu, Feb 10 '21 at 15:39
Well, why don't you post what you tried and post the errors you got? How are we supposed to help you with errors you don't post here? — nvoigt, Feb 10 '21 at 15:40
I did. I still have no idea what your code looks like. This is my final comment on this issue: *post your code and the errors that you have*. Preferably as a [mcve]. Otherwise we won't be able to help you. We cannot guess what you did wrong in your code if you don't show us your code. — nvoigt, Feb 10 '21 at 15:43
say , you want to convert Future to User in the same class ? — Kab Agouda, Feb 10 '21 at 15:48
You have not yet understood a core concept of dart, **asynchronous programming**. That is not a bad thing, nobody was born with an understanding of that concept, we all had to learn it at some point. You can read the link I provided, or you can read the links the answers provided, or you can read a good book or other teaching material of your choice. But you have to understand that there are no easy answers here. This is not a misplaced comma we can fix. It won't work the way you try it. You have to take the time and read up on the concept, understand it, and *then* find a solution. — nvoigt, Feb 10 '21 at 16:01

score 4 · Accepted Answer · edited Feb 10 '21 at 15:39

4

Just create an asynchronous function .

If you have Future<User>, to convert it to User, you need to add await; and to use await, you need to add async:

Future<void> test() async {
  User user = await fetchUser();
}

You can learn more about asynchronous function here

edited Feb 10 '21 at 15:39

nvoigt

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answered Feb 10 '21 at 13:00

Kab Agouda

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The operator '<' isn't defined for the type 'Type'. – umarbeyoglu Feb 10 '21 at 15:22
i have to get the user out of the Future async function to be able to assign it to "profile". Inside,it works – umarbeyoglu Feb 10 '21 at 15:51

score 0 · Answer 2 · answered Feb 10 '21 at 13:01

0

From where you are calling do this,

User user = await followingUserModel.fetchUser();

Future<User> means it will return an User object by asynchronously(in future), so make the call with await, then your code will wait till it get the return.

answered Feb 10 '21 at 13:01

shuvo

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I need to call it inside the class model that i am using.Can you instruct me more please? – umarbeyoglu Feb 10 '21 at 15:22
where are you calling fetchUser() function? Then why are you fetching data inside a model class? separate the responsibility of the classes. – shuvo Feb 11 '21 at 16:13

How can i convert Future to User in my class?

2 Answers2