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)

Using the HUD and Renderer classes

Declare an instance of the HUD and Renderer classes as members of the GameEngine class as highlighted in this next code:

class GameEngine extends SurfaceView implements Runnable,
GameStarter {
    private Thread mThread = null;
    private long mFPS;
    private GameState mGameState;
    private SoundEngine mSoundEngine;
    HUD mHUD;
    Renderer mRenderer;

Initialize the instances of the HUD and Renderer classes in the GameEngine constructor as highlighted next:

public GameEngine(Context context, Point size) {
      super(context);
      mGameState = new GameState(this, context);
      mSoundEngine = new SoundEngine(context);
      mHUD = new HUD(size);
      mRenderer = new Renderer(this);
}

Now we can add a call to the draw method of the Renderer class in the run method as highlighted next:

@Override
public void run() {
      while (mGameState.getThreadRunning()) {
          long frameStartTime = System.currentTimeMillis();
   ...