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

49.8 Designing the Menu

Within the Project tool window, locate the project’s app -> res -> menu -> menu_main.xml file and double-click on it to load it into the Layout Editor tool. Switch to Design mode if necessary and select and delete the default Settings menu item added by Android Studio so that the menu currently has no items.

From the palette, click and drag a menu group object onto the title bar of the layout canvas as highlighted in Figure 49-5:

Figure 49-5

Although the group item has been added, it will be invisible within the layout. To verify the presence of the element, refer to the Component Tree panel where the group will be listed as a child of the menu:

Figure 49-6

Select the group entry in the Component Tree and, referring to the Attributes panel, set the checkableBehavior property to single so that only one group menu item can be selected at any one time:

Figure 49-7

Next, drag four Menu Item elements from the palette...