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

83.11 Testing the Project

With the project now complete, run the app on a physical Android device or emulator session and click on the Authenticate button to display the BiometricPrompt dialog as shown in Figure 83-3:

Figure 83-3

Once running, either touch the fingerprint sensor or use the extended controls panel within the emulator to simulate a fingerprint touch as outlined in the chapter entitled “Using and Configuring the Android Studio AVD Emulator”. Assuming a registered fingerprint is detected the prompt dialog will return to the main activity where the toast message from the successful authentication callback method will appear.

Click the Authenticate button once again, this time using an unregistered fingerprint to attempt the authentication. This time the biometric prompt dialog will indicate that the fingerprint was not recognized:

Figure 83-4

Verify that the error handling callback is working by clicking on the activity outside of the...