Book Image

Android Studio 4.0 Development Essentials - Kotlin Edition

By : Neil Smyth
Book Image

Android Studio 4.0 Development Essentials - Kotlin Edition

By: Neil Smyth

Overview of this book

Kotlin as an Android-compatible programming language is becoming increasingly popular. Fully updated for Android Studio 4.0, this book will teach you the skills necessary to develop Android-based applications using Kotlin. Starting with the basics, this book outlines the steps necessary to set up Android development and testing environments, and goes on to introduce you to programming in Kotlin. You’ll practice Java to Kotlin code conversion and explore data types, operators, expressions, loops, functions, as well as the basics of OOP in Kotlin. You’ll then learn about Android architecture components and advanced topics, such as intents, touchscreen handling, gesture recognition, multi-window support integration, and biometric authentication. As you make progress, you’ll explore Android Studio 4.0’s key features, including layout editor, direct reply notifications, and dynamic delivery. You’ll also delve into Android Jetpack and create a sample app project using ViewModel, the Android Jetpack component. Finally, you will upload your app to Google Play Console and model the build process using Gradle. By the end of this Android book, you’ll be fully prepared to develop applications using Android Studio 4.0 and Kotlin.
Table of Contents (97 chapters)
97
Index

20.5 Lifetimes

The final topic to be covered involves an outline of the entire, visible and foreground lifetimes through which an activity or fragment will transition during execution:

Entire Lifetime –The term “entire lifetime” is used to describe everything that takes place between the initial call to the onCreate() method and the call to onDestroy() prior to the object terminating.

Visible Lifetime – Covers the periods of execution between the call to onStart() and onStop(). During this period the activity or fragment is visible to the user though may not be the object with which the user is currently interacting.

Foreground Lifetime – Refers to the periods of execution between calls to the onResume() and onPause() methods.

It is important to note that an activity or fragment may pass through the foreground and visible lifetimes multiple times during the course of the entire lifetime.

The concepts of lifetimes...