Book Image

Flutter Cookbook

By : Simone Alessandria, Brian Kayfitz
4 (1)
Book Image

Flutter Cookbook

4 (1)
By: Simone Alessandria, Brian Kayfitz

Overview of this book

“Anyone interested in developing Flutter applications for Android or iOS should have a copy of this book on their desk.” – Amazon 5* Review Lauded as the ‘Flutter bible’ for new and experienced mobile app developers, this recipe-based guide will teach you the best practices for robust app development, as well as how to solve cross-platform development issues. From setting up and customizing your development environment to error handling and debugging, The Flutter Cookbook covers the how-tos as well as the principles behind them. As you progress, the recipes in this book will get you up to speed with the main tasks involved in app development, such as user interface and user experience (UI/UX) design, API design, and creating animations. Later chapters will focus on routing, retrieving data from web services, and persisting data locally. A dedicated section also covers Firebase and its machine learning capabilities. The last chapter is specifically designed to help you create apps for the web and desktop (Windows, Mac, and Linux). Throughout the book, you’ll also find recipes that cover the most important features needed to build a cross-platform application, along with insights into running a single codebase on different platforms. By the end of this Flutter book, you’ll be writing and delivering fully functional apps with confidence.
Table of Contents (17 chapters)
About Packt

Using async/await to remove callbacks

Futures, with their then callbacks, allow developers to deal with asynchronous programming. There is an alternative pattern to deal with Futures that can help make your code cleaner and easier to read: the async/await pattern.

Several modern languages have this alternate syntax to simplify code, and at its core, it's based on two keywords: async and await:

  • async is used to mark a method as asynchronous, and it should be added before the function body.
  • await is used to tell the framework to wait until the function has finished its execution and returns a value. While the then callback works in any method, await only works inside async methods.

When you use await, the caller function must use the async modifier, and the function you call with await should also be marked as async.

What happens under the hood is that when you await an asynchronous function, the line of execution is stopped until the async operation completes.

Here, you can see...