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

How it works...

Cascades are pretty elegant. They allow you to chain methods together that were never intended to be chained. Dart is smart enough to know that all these consecutive lines of code are operating on the same object. Let's pick apart the numbers example:

final numbers = [342, 23423, 53, 232, 534]
..insert(0, 10)
..sort((a, b) => a.compareTo(b));

Both the insert and sort methods are void functions. Declaring these objects with cascades simply allows you to remove the call to the numbers object:

final numbers = [342, 23423, 53, 232, 534];
numbers.insert(0, 10);
numbers.sort((a, b) => a.compareTo(b));

With the cascade operator, you can merge unrelated statements in a simple fluent chain of function calls.

In our example, UrlBuilder is just a plain old Dart object. 

Without the cascade operator, we would have to write the same builder code like this:

final url = UrlBuilder();
url.scheme = 'https'; = '';
url.routes = ['guides', 'language', 'language-tour#cascade-notation-'];

But with cascades, that code can now be simplified, like so:

final url = UrlBuilder()
..scheme = 'https' = ''
..routes = ['guides', 'language', 'language-tour#cascade-notation-'];

Notice that this was accomplished without changing a single line in our class.