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

25.3 Using Apply Changes

When a project has been loaded into Android Studio, but is not yet running on a device or emulator, it can be launched as usual using either the run (marked A in Figure 25-1) or debug (B) button located in the toolbar:

Figure 25-1

After the app has launched and is running, the icon on the run button will change to indicate that the app is running and the Apply Changes and Restart Activity and Apply Code Changes buttons will be enabled as indicated in Figure 25-2 below:

Figure 25-2

If the changes are unable to be applied when one of the Apply Changes buttons is selected, Android Studio will display a message indicating the failure together with an explanation. Figure 25-3, for example, shows the message displayed by Android Studio when the Apply Code Changes option is selected after a change has been made to a resource file:

Figure 25-3

In this situation, the solution is to use the Apply Changes and Restart Activity option (for...