Book Image

Android Programming for Beginners

By : John Horton, Paresh Mayani
Book Image

Android Programming for Beginners

By: John Horton, Paresh Mayani

Overview of this book

Android is the most popular OS in the world. There are millions of devices accessing tens of thousands of applications. It is many people's entry point into the world of technology; it is an operating system for everyone. Despite this, the entry-fee to actually make Android applications is usually a computer science degree, or five years’ worth of Java experience. Android Programming for Beginners will be your companion to create Android applications from scratch—whether you’re looking to start your programming career, make an application for work, be reintroduced to mobile development, or are just looking to program for fun. We will introduce you to all the fundamental concepts of programming in an Android context, from the Java basics to working with the Android API. All examples are created from within Android Studio, the official Android development environment that helps supercharge your application development process. After this crash-course, we’ll dive deeper into Android programming and you’ll learn how to create applications with a professional-standard UI through fragments, make location-aware apps with Google Maps integration, and store your user’s data with SQLite. In addition, you’ll see how to make your apps multilingual, capture images from a device’s camera, and work with graphics, sound, and animations too. By the end of this book, you’ll be ready to start building your own custom applications in Android and Java.
Table of Contents (37 chapters)
Android Programming for Beginners
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Entering the nth dimension with arrays


We very briefly mentioned that an array can even hold other arrays at each position. And of course, if an array holds lots of arrays that hold lots of some other type, how do we access the values in the contained arrays? And why would we ever need this anyway? Take a look at this next example where multidimensional arrays can be useful.

A multidimensional array mini app

Let's make a really simple multidimensional array example. You can get the working project for this example in the download bundle. It is located at Chapter 13/Multidimensional Array Example/MainActivity.java.

Create a project with a blank Activity and call it Multidimensional Array Example.

After the call to setContentView in onCreate, declare and initialize a two-dimensional array like this:

// Random object for generating question numbers
Random randInt = new Random();
// a variable to hold the random value generated
int questionNumber;

// declare and allocate in separate stages for clarity...