Book Image

Android Studio 4.0 Development Essentials - Java Edition

By : Neil Smyth
Book Image

Android Studio 4.0 Development Essentials - Java Edition

By: Neil Smyth

Overview of this book

Android rolls out frequent updates to meet the demands of the dynamic mobile market and to enable its developer community to lead advancements in application development. This book focuses on the updated features of Android Studio (the fully integrated development environment launched by Google) to build reliable Android applications using Java. The book starts by outlining the steps necessary to set up an Android development and testing environment. You’ll then learn how to create user interfaces with the help of Android Studio Layout Editor, XML files, and by writing the code in Java. The book introduces you to Android architecture components and advanced topics such as intents, touchscreen handling, gesture recognition, multi-window support integration, and biometric authentication, and lets you explore key features of Android Studio 4.0, including the layout editor, direct reply notifications, and dynamic delivery. You’ll also cover Android Jetpack in detail and create a sample app project using the ViewModel component. Finally, you’ll upload your app to the Google Play Console and handle the build process with Gradle. By the end of this book, you’ll have gained the skills necessary to develop applications using Android Studio 4.0 and Java.
Table of Contents (88 chapters)
88
Index

70.3 Designing the User Interface

The user interface will need to be comprised of three Button views and a single EditText view. Within the Project tool window, navigate to the activity_main.xml layout file located in app -> res -> layout and double-click on it to load it into the Layout Editor tool. With the tool in Design mode, select and delete the Hello World! TextView object.

Drag and position a Button widget in the top left-hand corner of the layout so that both the left and top dotted margin guidelines appear before dropping the widget in place. Position a second Button such that the center and top margin guidelines appear. The third Button widget should then be placed so that the top and right-hand margin guidelines appear.

Change the text attributes on the three buttons to “New”, “Open” and “Save” respectively. Next, position a Plain Text widget so that it is centered horizontally and positioned beneath the center Button...