Book Image

Learning Java by Building Android Games - Second Edition

By : John Horton
Book Image

Learning Java by Building Android Games - Second Edition

By: John Horton

Overview of this book

Android is one of the most popular mobile operating systems presently. It uses the most popular programming language, Java, as the primary language for building apps of all types. However, this book is unlike other Android books in that it doesn’t assume that you already have Java proficiency. This new and expanded second edition of Learning Java by Building Android Games shows you how to start building Android games from scratch. The difficulty level will grow steadily as you explore key Java topics, such as variables, loops, methods, object oriented programming, and design patterns, including code and examples that are written for Java 9 and Android P. At each stage, you will put what you’ve learned into practice by developing a game. You will build games such as Minesweeper, Retro Pong, Bullet Hell, and Classic Snake and Scrolling Shooter games. In the later chapters, you will create a time-trial, open-world platform game. By the end of the book, you will not only have grasped Java and Android but will also have developed six cool games for the Android platform.
Table of Contents (30 chapters)
Learning Java by Building Android Games Second Edition
Contributors
Preface
Index

Implementing the game loop with a thread


Now we have learned about the game loop, threads, try and catch, we can put it all together to implement our game loop.

We will add the entire code for the game loop including writing two methods in the PongGame class to start and stop the thread which will control the loop.

After we have done this we will again need to do a little bit more theory. The reason for this is that the player can quit the app whenever they like, and our game's thread will need to know so it can stop itself. We will examine the Android Activity lifecycle which will give us the final pieces of the puzzle that we need before we run our game.

Implementing Runnable and providing the run method

Update the class declaration by implementing Runnable, just like we discussed we would need to and as shown in this next highlighted code.

class PongGame extends SurfaceView implements Runnable{

Notice that we have a new error in the code. Hover the mouse pointer over the word Runnable and...