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

Controlling loops with break and continue


Having just discussed all the ways that we can control looping through code, it is important to know that sometimes we need to break out of a loop earlier than the condition of the loop specifies.

For such occasions, Kotlin has the break keyword. Here is break in action with a while loop:

var countDown = 10
while(countDown > 0){

  if(countDown == 5)break

  Log.i("countDown =","$countDown")
  countDown --
}

In the preceding code, the condition of the while loop should make the code repeatedly execute while the countDown variable is greater than zero. However, inside the while loop, there is an if expression that checks to see whether countDown is equal to 5. If it is equal to 5, the break statement is used. Also, inside the while loop, the value of countDown is printed to the logcat window and is decremented (reduced by 1). Take a look at the following output when this code is executed:

countDown =: 10
countDown =: 9
countDown =: 8
countDown =:...