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

30.4 Adding and Managing Fragments in Code

The ease of adding a fragment to an activity via the activity’s XML layout file comes at the cost of the activity not being able to remove the fragment at runtime. In order to achieve full dynamic control of fragments during runtime, those activities must be added via code. This has the advantage that the fragments can be added, removed and even made to replace one another dynamically while the application is running.

When using code to manage fragments, the fragment itself will still consist of an XML layout file and a corresponding class. The difference comes when working with the fragment within the hosting activity. There is a standard sequence of steps when adding a fragment to an activity using code:

1. Create an instance of the fragment’s class.

2. Pass any additional intent arguments through to the class instance.

3. Obtain a reference to the fragment manager instance.

4. Call the beginTransaction() method...