Book Image

Android Studio 4.1 Development Essentials – Java Edition

By : Neil Smyth
Book Image

Android Studio 4.1 Development Essentials – Java Edition

By: Neil Smyth

Overview of this book

For developers, Android 11 has a ton of new capabilities. The goal of this book is to teach the skills necessary to develop Android-based applications using the Java programming language. This book begins with the steps necessary to set up an Android development and testing environment. An overview of Android Studio along with the architecture of Android is covered next, followed by an in-depth look at the design of Android applications and user interfaces using the Android Studio environment. You will also learn about the Android architecture components along with some advanced topics such as touch screen handling, gesture recognition, the recording and playback of audio, app links, dynamic delivery, the AndroidStudio profiler, Gradle build configuration, and submitting apps to the Google Play Developer Console. The concepts of material design, including the use of floating action buttons, Snackbars, tabbed interfaces, card views, navigation drawers, and collapsing toolbars are a highlight of this book. This edition of the book also covers printing, transitions, and cloud-based file storage; the foldable device support is the cherry on the cake. By the end of this course, you will be able to develop Android 11 Apps using Android Studio 4.1, Java, and Android Jetpack. The code files for the book can be found here: https://www.ebookfrenzy.com/retail/androidstudio41/index.php
Table of Contents (88 chapters)
88
Index

59.8 Modifying the User Interface

As will become evident when the application runs, failing to create a new thread for the service to perform tasks creates a serious usability problem. In order to be able to appreciate fully the magnitude of this issue, it is going to be necessary to add a Button view to the user interface of the MainActivity and configure it to call a method when “clicked” by the user.

Locate and load the activity_main.xml file in the Project tool window (app -> res -> layout -> activity_main.xml). Delete the TextView and add a Button view to the layout. Select the new button, change the text to read “Start Service” and extract the string to a resource named start_service.

With the new Button still selected, locate the onClick property in the Attributes panel and assign to it a method named buttonClick.

Next, edit the MainActivity.java file to add the buttonClick() method and remove the code from the onCreate() method...