example2

example2.dart

import 'package:flutter/material.dart';

void main() =>
    runApp(MaterialApp(home: Scaffold(body: Center(child: MyWidget()))));

Future<String> callAsyncFetch() =>
    Future.delayed(Duration(seconds: 3), () => "hi bro !");

class MyWidget extends StatelessWidget {
  @override
  Widget build(context) {
    return FutureBuilder<String>(
        future: callAsyncFetch(),
        builder: (context, AsyncSnapshot<String> snapshot) {
          if (snapshot.hasData) {
            return Text(snapshot.data);
          } else {
            return CircularProgressIndicator();
          }
        });
  }
}