//services.dart
Future<List<Post>> getAllPosts() async {
  final response = await http.get(url);
  return allPostsFromJson(response.body);
}

// As a part of your UI widget, e.g body of Scaffold widget
FutureBuilder<List<Post>>(
            future: getAllPosts(),
            builder: (context, snapshot) {
              if(snapshot.hasData)
                return Text('Title from Post JSON : ${snapshot.data[0].title}');
              else
                return CircularProgressIndicator();
            }
        )

//services.dart
Future<Post> getPost() async{
  final response = await http.get('$url/1'); // the number is the id of the item being accessed
  return postFromJson(response.body);
}

// As a part of your UI widget, e.g body of Scaffold widget
FutureBuilder<Post>(
            future: getPost(),
            builder: (context, snapshot) {
              if(snapshot.hasData)
                return Text('Title from Post JSON : ${snapshot.data.title}');
              else
                return CircularProgressIndicator();
            }
        )

//services.dart
Future<http.Response> createPost(Post post) async{
  final response = await http.post('$url',
      headers: {
        HttpHeaders.contentTypeHeader: 'application/json'
      },
      body: postToJson(post)
  );

  return response;
}

  //call this function when you want to create a new post
 callAPI(){
    Post post = Post(
      body: 'Testing body body body',
      title: 'Flutter jam6'
    ); // creating a new Post object to send it to API
    
    createPost(post).then((response){
        if(response.statusCode > 200)
          print(response.body);
        else
          print(response.statusCode);
    }).catchError((error){
      print('error : $error');
    });
    
  }