Forrester / Miles / Dumbravan How to Build Android Applications with Kotlin

A hands-on guide to developing, testing, and publishing production-grade Android 16 apps
3. Auflage 2025
ISBN: 978-1-83588-277-1
Verlag: De Gruyter
Format: EPUB
Kopierschutz: 0 - No protection

E-Book, Englisch, 654 Seiten

Written by four veteran developers with 60+ years of collective experience, this updated third edition will jumpstart your Android development journey, focusing on Kotlin libraries and Jetpack Compose, Google's powerful declarative UI framework.
You'll learn the fundamentals of app development, enabling you to use Android Studio, as well as get to grips with Jetpack Compose to create your first screens, build apps to run them on virtual devices through guided exercises, and implement Jetpack Compose's layout groups to make the most of lists, images, and maps. The book has been updated with Kotlin's powerful networking and coroutines libraries to help you fetch data in the background from a web service and manage displaying the data using Kotlin flows. You'll learn about testing, creating clean architecture, and persisting data, as well as exploring the dependency injection pattern and learning how to publish your apps on the Google Play Store. You'll also work on realistic projects split up into bite-size exercises and activities, along with building 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 gained the skills and confidence to build your own creative Android apps using Kotlin.

Autoren/Hrsg.

Forrester, Alex

Miles, Steve

Dumbravan, Alexandru

Fridberg, Alice

Fachgebiete

• Mathematik | Informatik EDV | Informatik Betriebssysteme

Leseproben

1

Creating Your First App

This chapter is an introduction to Android, where you will set up the Android Studio environment and focus on the fundamentals of Android development.

You will cover creating an Android project with Android Studio. Then, you will set up a virtual device and run your app on it. You will explore the Android manifest file, which details all the Android app components, features, and permissions model. You will learn how to use the Gradle build system and analyze the Android application structure. You will start developing user interfaces (UIs) with the Android UI toolkit, Jetpack Compose.

By the end of this chapter, you will have gained the knowledge required to create an Android app from scratch and install it on a virtual Android device. You will be able to analyze and understand the importance of the file. You will know how an app project is structured in Android Studio and use the Gradle build tool to configure and build your app and manage library dependencies. Finally, you will be able to start implementing UI elements using Jetpack Compose with Material Design.

We will cover the following topics in the chapter:

• Creating an Android project with Android Studio
• Setting up a virtual device and running your app
• The Android manifest file
• Using Gradle to build, configure, and manage app dependencies
• Android application structure

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Creating an Android project with Android Studio

In order to be productive building Android apps, it is essential to become confident in using Android Studio. This is the official integrated development environment (IDE) for Android development, built on JetBrains’ IntelliJ IDEA IDE and developed by the Android Studio team at Google. You will use it throughout this book to create apps and progressively add more advanced features.

Since Google I/O 2017 (the annual Google developer conference), Kotlin has been Google’s preferred programming language for Android app development. You will be using Kotlin throughout this book to build Android apps.

Kotlin was created to address some of the shortcomings of Java in terms of verbosity, handling null types, and adding more functional programming techniques, among many other issues.

Getting to grips with and familiarizing yourself with Android Studio will enable you to feel confident building Android apps. So, let’s get started with creating your first project.

The installation and setup of Android Studio are covered in the . Please ensure you have completed those steps before you continue.

Exercise 1.01 – Creating an Android Studio project for your app

This is the starting point for creating a project structure that your app will be built upon. The template-driven approach will enable you to create a basic project in a short timeframe while setting up the building blocks you can use to develop your app.

To complete this exercise, perform the following steps:

1. Open Android Studio. You will see a window with side tabs and Projects highlighted. Select the New Project option on the right-hand side.
2. Now, you’ll enter a simple wizard-driven flow, which greatly simplifies the creation of your first Android project. The next screen you will see has many options for the initial setup you’d like your app to have:

Figure 1.4 – Starting a project template for your app

Welcome to your first introduction to the Android development ecosystem. The word displayed in most of the project types is . In Android, an activity represents a single screen in your app that a user can interact with. When creating a new project, you can choose from different templates, each of which sets up the initial screen in a specific way. These templates determine how the first screen will look and provide a starting point for building your app. Select Empty Activity from the template and click on Next. The project configuration screen is as follows:

Figure 1.5 – Project configuration

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The preceding screen configures your app. Let’s go through all the options:

• Name: Similar to the name of your Android project, this name will appear as the default name of your app when it’s installed on a phone and visible on Google Play.
• Package name: This uses the standard reverse domain name pattern to create a name. It will be used as an address identifier for source code and assets in your app. It’s best to make this name as clear and descriptive and as closely aligned with the purpose of your app as possible. As shown in , the Name value of the app, (in lowercase with spaces removed), is appended to the domain ().
• Save location: This is the local folder on your machine where the app will initially be stored. By default, the project will be saved into a new folder with the name of the application with spaces removed. This results in a project folder being created.
• Minimum SDK: Depending on which version of Android Studio you download, the default might be the same as shown in or a...