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Learning Java by Building Android Games

You're reading from   Learning Java by Building Android Games Learn Java and Android from scratch by building five exciting games

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Product type Paperback
Published in Mar 2021
Publisher Packt
ISBN-13 9781800565869
Length 686 pages
Edition 3rd Edition
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Author (1):
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John Horton John Horton
Author Profile Icon John Horton
John Horton
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Toc

Table of Contents (24) Chapters Close

Preface 1. Chapter 1: Java, Android, and Game Development 2. Chapter 2: Java – First Contact FREE CHAPTER 3. Chapter 3: Variables, Operators, and Expressions 4. Chapter 4: Structuring Code with Java Methods 5. Chapter 5: The Android Canvas Class – Drawing to the Screen 6. Chapter 6: Repeating Blocks of Code with Loops 7. Chapter 7: Making Decisions with Java If, Else, and Switch 8. Chapter 8: Object-Oriented Programming 9. Chapter 9: The Game Engine, Threads, and the Game Loop 10. Chapter 10: Coding the Bat and Ball 11. Chapter 11: Collisions, Sound Effects, and Supporting Different Versions of Android 12. Chapter 12: Handling Lots of Data with Arrays 13. Chapter 13: Bitmap Graphics and Measuring Time 14. Chapter 14: Java Collections, the Stack, the Heap, and the Garbage Collector 15. Chapter 15: Android Localization – Hola! 16. Chapter 16: Collections and Enumerations 17. Chapter 17: Manipulating Bitmaps and Coding the Snake Class 18. Chapter 18: Introduction to Design Patterns and Much More! 19. Chapter 19: Listening with the Observer Pattern, Multitouch, and Building a Particle System 20. Chapter 20: More Patterns, a Scrolling Background, and Building the Player's Ship 21. Chapter 21: Completing the Scrolling Shooter Game 22. Chapter 22: What Next? 23. Other Books You May Enjoy

Using the Canvas class

Let's look at the code and the different stages required to get drawing, and then we can quickly move on to drawing something for real, with the help of the Canvas demo app.

Preparing the objects of classes

Remember, back in Chapter 2, Java – First Contact, that I said the following:

In Java, a blueprint is called a class. When a class is transformed into a real working thing, we call it an object or an instance of the class.

The first step is to turn the classes (blueprints) we need into real working things – objects/instances. This step is analogous to declaring variables.

Important note

We have already done this with the Random class in the previous chapter and will explore this in more depth in Chapter 8, Object-Oriented Programming.

First, we state the type, which in this case happens to be a class, and then we state the name we would like our working object to have:

// Here are all the objects(instances)
// of...
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