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

57.9 Running the Application

Run the application and, once loaded, touch the Start Service button. Within the Logcat tool window (using the ServiceExample filter created previously) the log messages will appear indicating that the onCreate() method was called and that the loop in the onStartCommand() method is executing.

Before the final loop message appears, attempt to touch the Start Service button a second time. Note that the button is unresponsive. After approximately 20 seconds, the system may display a warning dialog containing the message “ServiceExample isn’t responding”. The reason for this is that the main thread of the application is currently being held up by the service while it performs the looping task. Not only does this prevent the application from responding to the user, but also to the system, which eventually assumes that the application has locked up in some way.

Clearly, the code for the service needs to be modified to perform tasks...