Book Image

How to Build Android Apps with Kotlin - Second Edition

By : Alex Forrester, Eran Boudjnah, Alexandru Dumbravan, Jomar Tigcal
Book Image

How to Build Android Apps with Kotlin - Second Edition

By: Alex Forrester, Eran Boudjnah, Alexandru Dumbravan, Jomar Tigcal

Overview of this book

Looking to kick-start your app development journey with Android 13, but don’t know where to start? How to Build Android Apps with Kotlin is a comprehensive guide that will help jump-start your Android development practice. This book starts with the fundamentals of app development, enabling you to utilize Android Studio and Kotlin to get started with building Android projects. You'll learn how to create apps and run them on virtual devices through guided exercises. Progressing through the chapters, you'll delve into Android's RecyclerView to make the most of lists, images, and maps, and see how to fetch data from a web service. You'll also get to grips with testing, learning how to keep your architecture clean, understanding how to persist data, and gaining basic knowledge of the dependency injection pattern. Finally, you'll see how to publish your apps on the Google Play store. You'll work on realistic projects that are split up into bitesize exercises and activities, allowing you to challenge yourself in an enjoyable and attainable way. You'll build apps to create quizzes, read news articles, check weather reports, store recipes, retrieve movie information, and remind you where you parked your car. By the end of this book, you'll have the skills and confidence to build your own creative Android applications using Kotlin.
Table of Contents (24 chapters)
1
Part 1: Android Foundation
6
Part 2: Displaying Network Calls
12
Part 3: Testing and Code Structure
17
Part 4: Polishing and Publishing an App

Dynamic fragments

So far, you’ve only seen fragments added in XML at compile time. Although this can satisfy many use cases, you might want to add fragments dynamically at runtime to respond to the user’s actions. This can be achieved by adding ViewGroup as a container for fragments and then adding, replacing, and removing fragments from ViewGroup.

This technique is more flexible as the fragments can be active until they are no longer needed and then removed, instead of always being inflated in XML layouts as you have seen with static fragments. If three or four more fragments are required to fulfill separate user journeys in one activity, then the preferred option is to react to the user’s interaction in the UI by adding/replacing fragments dynamically.

Using static fragments works better when the user’s interaction with the UI is fixed at compile time and you know in advance how many fragments you need. For example, this would be the case for selecting...