Book Image

How to Build Android Apps with Kotlin

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

How to Build Android Apps with Kotlin

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

Overview of this book

Are you keen to get started building Android 11 apps, but don’t know where to start? How to Build Android Apps with Kotlin is a comprehensive guide that will help kick-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 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. Moving ahead, you'll get to grips with testing, learn how to keep your architecture clean, understand how to persist data, and gain 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 (17 chapters)
Preface
12
12. Dependency Injection with Dagger and Koin

Summary

In this chapter, we analyzed the building blocks required to build a maintainable application. We also looked into one of the most common issues that developers come across when using the Android Framework, which is maintaining the states of objects during life cycle changes.

We started by analyzing ViewModels and how they solve the issue of holding data during orientation changes. We added LiveData to ViewModels to show how the two complement each other.

We then moved on to Room to show how we can persist data with minimal effort and without a lot of SQLite boilerplate code. We also explored one-to-many and many-to-many relationships, as well as how to migrate data and break down complex objects into primitives for storage.

After that, we reinvented the Lifecycle wheel in order to show how LifecycleOwners and LifecycleObservers interact.

We also built our first repository, which we will expand upon in the following chapters when other data sources are added into...