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

28.3 Preparing the Layout Editor Environment

Locate and double-click on the activity_main.xml layout file located in the app -> res -> layout folder to load it into the Layout Editor tool. Since the purpose of this tutorial is to gain experience with the use of constraints, turn off the Autoconnect feature using the button located in the Layout Editor toolbar. Once disabled, the button will appear with a line through it as is the case in Figure 28-2:

Figure 28-2

If the default margin value to the right of the Autoconnect button is not set to 8dp, click on it and select 8dp from the resulting panel.

The user interface design will also make use of the ImageView object to display an image. Before proceeding, this image should be added to the project ready for use later in the chapter. This file is named galaxys6.png and can be found in the project_icons folder of the sample code download available from the following URL:

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