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

27.1 Creating a Chain

Chains may be implemented either by adding a few lines to the XML layout resource file of an activity or by using some chain specific features of the Layout Editor.

Consider a layout consisting of three Button widgets constrained so as to be positioned in the top-left, top-center and top-right of the ConstraintLayout parent as illustrated in Figure 27-1:

Figure 27-1

To represent such a layout, the XML resource layout file might contain the following entries for the button widgets:

<Button

    android:id="@+id/button1"

    android:layout_width="wrap_content"

    android:layout_height="wrap_content"

    android:layout_marginStart="8dp"

    android:layout_marginTop="16dp"

    android:text="Button"

    app:layout_constraintHorizontal_bias...