Book Image

Learning Java by Building Android Games - Third Edition

By : John Horton
5 (1)
Book Image

Learning Java by Building Android Games - Third Edition

5 (1)
By: John Horton

Overview of this book

Android is one of the most popular mobile operating systems today. It uses the most popular programming language, Java, as one of the primary languages for building apps of all types. Unlike most other Android books, this book doesn’t assume that you have any prior knowledge of Java programming, instead helps you get started with building Android games as a beginner. This new, improved, and updated third edition of Learning Java by Building Android Games helps you to build Android games from scratch. Once you've got to grips with the fundamentals, the difficulty level increases steadily as you explore key Java topics, such as variables, loops, methods, object-oriented programming (OOP), and design patterns while working with up-to-date code and supporting examples. At each stage, you'll be able to test your understanding by implementing the concepts that you’ve learned to develop a game. Toward the end, you’ll build games such as Sub Hunter, Retro Pong, Bullet Hell, Classic Snake, and Scrolling Shooter. By the end of this Java book, you'll not only have a solid understanding of Java and Android basics but will also have developed five cool games for the Android platform.
Table of Contents (24 chapters)

The Bat class

The Bat class, as we will see, has several similarities to the Ball class. After all, it's just a moving rectangle. However, the bat in the game needs to be controlled by the player. So, we need to provide a way to communicate what the player is pressing on the screen to the Bat class.

In later projects with more complicated controls, we will let the class itself translate the screen presses. For the Bat class, we will let the PongGame class handle the touches and just let the Bat class know one of three things: move left, move right, don't move. Let's look at all the variables the Bat class is going to need.

We will need a RectF instance to hold the position of the bat and a way of sharing the details with the PongGame class. We will call this variable mRect and the solution to sharing it will be identical to the solution from the Ball class – a default access getRect method that returns a RectF object.

We will need to calculate and retain...