Aprenda Delays and Future.delayed | Futures and async/await

When you need to introduce a pause or simulate a time-consuming operation in Dart asynchronous code, you can use Future.delayed. This constructor creates a Future that completes after a specified duration. It is commonly used to mimic network requests, database calls, or any operation where you want to wait before continuing your code.

The Future.delayed constructor takes two parameters:

The first parameter is a Duration object, which specifies how long the delay should be;
The second parameter is an optional callback function that returns the value with which the Future will complete.

By using await with Future.delayed, you can pause the execution of an async function for a given amount of time, making your code easier to read and control.

main.dart


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import 'dart:async';

Future<String> fetchData() async {
  // Simulate a 2-second network delay
  return await Future.delayed(
    Duration(seconds: 2),
    () => 'Data loaded',
  );
}

void main() async {
  print('Requesting data...');
  String result = await fetchData();
  print(result);
}

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