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)
16
About Packt

How it works...

StatefulWidgets are made up of two classes: the widget and the state. The widget part of StatefulWidget really doesn't do much, and all the properties that you store in it must be final; otherwise, you will get a compile error.


All widgets, whether they are stateless or stateful, are still immutable. In Stateful widgets, the state can change.

What doesn't have to be immutable is the State object. The State object takes over the build responsibilities from the widget. States can also be marked as dirty, which is what will cause them to repaint on the next frame. Take a close look at this line:

setState(() {
++seconds;
});

The setState function tells Flutter that a widget needs to be repainted. In this specific example, we are incrementing the seconds property by one, which means that when the build function is called again, it will replace the Text widget with different content. 


Each time you call setState...