Book Image

How to Build Android Apps with Kotlin - Second Edition

By : Alex Forrester, Eran Boudjnah, Alexandru Dumbravan, Jomar Tigcal
5 (1)
Book Image

How to Build Android Apps with Kotlin - Second Edition

5 (1)
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

Getting started with MVVM

MVVM allows you to separate the UI and business logic. When you need to redesign the UI or update the Model/business logic, you only need to touch the relevant component without affecting the other components of your app. This will make it easier for you to add new features and test your existing code. MVVM is also useful in creating huge applications that use a lot of data and views.

With the MVVM architectural pattern, your application will be grouped into three components:

  • Model: This represents the data layer
  • View: This is the UI that displays the data
  • ViewModel: This fetches data from Model and provides it to View

The MVVM architectural pattern can be understood better through the following diagram:

Figure 15.1 – The MVVM architectural pattern

Figure 15.1 – The MVVM architectural pattern

The Model contains the data of the application. The activities, fragments, and layouts that your users see and interact with are the Views in MVVM....