How can I “sleep” a Dart program

Question

I like to simulate an asynchronous web service call in my Dart application for testing. To simulate the randomness of these mock calls responding (possibly out of order) I\

Answer 1

You can also use the Future.delayed factory to complete a future after a delay. Here is an example of two functions that return a string asynchronously after a delay:

import 'dart:async';

Future sleep1() {
  return new Future.delayed(const Duration(seconds: 1), () => "1");
}

Future sleep2() {
  return new Future.delayed(const Duration(seconds: 2), () => "2");
}