Book Image

Android Studio 3.5 Development Essentials - Java Edition

By : Neil Smyth
Book Image

Android Studio 3.5 Development Essentials - Java Edition

By: Neil Smyth

Overview of this book

Android applications have become an important part of our daily lives and lots of effort goes into developing an Android application. This book will help you to build you own Android applications using Java. Android Studio 3.5 Development Essentials – Java Edition first teaches you to install Android development and test environment on different operating systems. Next, you will create an Android app and a virtual device in Android Studio, and install an Android application on emulator. You will test apps on physical Android devices, then study Android Studio code editor and constraint layout, Android architecture, the anatomy of an Android app, and Android activity state changes. The book then covers advanced topics such as views and widgets implementation, multi-window support integration, and biometric authentication, and finally, you will learn to upload your app to Google Play console and handle the build process with Gradle. By the end of this book, you will have gained enough knowledge to develop powerful Android applications using Java.
Table of Contents (86 chapters)
86
Index

48. A Layout Editor Sample Data Tutorial

The CardDemo project created in the previous chapter has provided a good example of how it can be difficult to assess from within the layout editor exactly how a user interface is going to appear until the completed app is tested. This is a problem that frequently occurs when the content to be displayed in a user interface is only generated or acquired once the user has the app installed and running.

For some time now, the Android Studio layout editor has provided the ability to specify simple attributes that are active only when the layout is being designed. A design-time only string resource could, for example, be assigned to a TextView within the layout editor that would not appear when the app runs. This capability has been extended significantly with the introduction of sample data support within the Android Studio layout editor and will be used in this chapter to improve the layout editor experience in the CardDemo project.