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

ArrayLists


ArrayList is like a regular Java array on steroids. It overcomes some of the shortfalls of arrays such as having to predetermine its size. It adds some really useful methods to make its data easy to manage, and it uses an enhanced version of a for loop, which is clearer to use than a regular for loop.

Let's look at some code that uses ArrayList:

// Declare a new ArrayList called myList to hold int variables
ArrayList<int> myList;
 
// Initialize the myList ready for use
myList = new ArrayList<int>();

In the previous code, we declared and initialized a new ArrayList called myList. We can also do this in a single step as shown in the following code:

ArrayList<int> myList = new ArrayList<int>();

We have seen nothing especially interesting so far, so let's take a look at what we can actually do with ArrayList. Let's use String ArrayList this time:

// declare and initialize a new ArrayList
ArrayList<String> myList = new ArrayList<String>();

// Add a...