Book Image

Hands-On Android UI Development

By : Jason Morris
Book Image

Hands-On Android UI Development

By: Jason Morris

Overview of this book

A great user interface (UI) can spell the difference between success and failure for any new application. This book will show you not just how to code great UIs, but how to design them as well. It will take novice Android developers on a journey, showing them how to leverage the Android platform to produce stunning Android applications. Begin with the basics of creating Android applications and then move on to topics such as screen and layout design. Next, learn about techniques that will help improve performance for your application. Also, explore how to create reactive applications that are fast, animated, and guide the user toward their goals with minimal distraction. Understand Android architecture components and learn how to build your application to automatically respond to changes made by the user. Great platforms are not always enough, so this book also focuses on creating custom components, layout managers, and 2D graphics. Also, explore many tips and best practices to ease your UI development process. By the end, you'll be able to design and build not only amazing UIs, but also systems that provide the best possible user experience.
Table of Contents (21 chapters)
Title Page
Credits
About the Author
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface
13
Activity Lifecycle

Creating a layout implementation


In most applications, you'll find that a combination of the ConstraintLayout, CoordinatorLayout, and some of the more primitive layout classes (such as LinearLayout and FrameLayout)) are more than enough to achieve any layout requirements you can dream up for your user interface. Every now and again though, you'll find yourself needing a custom layout manager to achieve an effect required for the application.

Layout classes extend from the ViewGroup class, and their job is to tell their child widgets where to position themselves, and how large they should be. They do this in two phases: the measurement phase and the layout phase.

All View implementations are expected to provide measurements for their actual size according to specifications. These measurements are then used by the View widget's parent ViewGroup to allocate the amount of space the widget will consume on the screen. For example, a View might be told to consume, at most, the screen width. The View...