Book Image

Android Programming with Kotlin for Beginners

By : John Horton
5 (1)
Book Image

Android Programming with Kotlin for Beginners

5 (1)
By: John Horton

Overview of this book

Android is the most popular mobile operating system in the world and Kotlin has been declared by Google as a first-class programming language to build Android apps. With the imminent arrival of the most anticipated Android update, Android 10 (Q), this book gets you started building apps compatible with the latest version of Android. It adopts a project-style approach, where we focus on teaching the fundamentals of Android app development and the essentials of Kotlin by building three real-world apps and more than a dozen mini-apps. The book begins by giving you a strong grasp of how Kotlin and Android work together before gradually moving onto exploring the various Android APIs for building stunning apps for Android with ease. You will learn to make your apps more presentable using different layouts. You will dive deep into Kotlin programming concepts such as variables, functions, data structures, Object-Oriented code, and how to connect your Kotlin code to the UI. You will learn to add multilingual text so that your app is accessible to millions of more potential users. You will learn how animation, graphics, and sound effects work and are implemented in your Android app. By the end of the book, you will have sound knowledge about significant Kotlin programming concepts and start building your own fully featured Android apps.
Table of Contents (33 chapters)
Android Programming with Kotlin for Beginners
Contributors
Preface
Index

Coding messages to the user and the developer


In the introduction to this chapter and in the previous chapter, we talked a bit about using other people's code, specifically via the classes and their functions of the Android API. We saw that we could do some quite complex things with fairly insignificant amounts of code (such as talking to satellites).

To get us started on coding, we are going to use two different classes from the Android API that allow us to output messages. The first class, Log, allows us to output messages to the logcat window. The second class, Toast, is not a tasty breakfast treat, but it will produce a toast-shaped pop up message for our app's user to see.

Here is the code we need to write to send a message to logcat:

Log.i("info","our message here")

Exactly why this works will become clearer in Chapter 10, Object-Oriented Programming, but for now, we just need to know that whatever we put between the two sets of quote marks will be output to the logcat window. We will...