Book Image

Android Studio 4.0 Development Essentials - Kotlin Edition

By : Neil Smyth
Book Image

Android Studio 4.0 Development Essentials - Kotlin Edition

By: Neil Smyth

Overview of this book

Kotlin as an Android-compatible programming language is becoming increasingly popular. Fully updated for Android Studio 4.0, this book will teach you the skills necessary to develop Android-based applications using Kotlin. Starting with the basics, this book outlines the steps necessary to set up Android development and testing environments, and goes on to introduce you to programming in Kotlin. You’ll practice Java to Kotlin code conversion and explore data types, operators, expressions, loops, functions, as well as the basics of OOP in Kotlin. You’ll then learn about Android architecture components and advanced topics, such as intents, touchscreen handling, gesture recognition, multi-window support integration, and biometric authentication. As you make progress, you’ll explore Android Studio 4.0’s key features, including layout editor, direct reply notifications, and dynamic delivery. You’ll also delve into Android Jetpack and create a sample app project using ViewModel, the Android Jetpack component. Finally, you will upload your app to Google Play Console and model the build process using Gradle. By the end of this Android book, you’ll be fully prepared to develop applications using Android Studio 4.0 and Kotlin.
Table of Contents (97 chapters)
97
Index

38.1 About the Example Fragment Application

The application created in this chapter will consist of a single activity and two fragments. The user interface for the first fragment will contain a toolbar of sorts consisting of an EditText view, a SeekBar and a Button, all contained within a ConstraintLayout view. The second fragment will consist solely of a TextView object, also contained within a ConstraintLayout view.

The two fragments will be embedded within the main activity of the application and communication implemented such that when the button in the first fragment is pressed, the text entered into the EditText view will appear on the TextView of the second fragment using a font size dictated by the position of the SeekBar in the first fragment.

Since this application is intended to work on earlier versions of Android, it will also be necessary to make use of the appropriate Android support library.