1. www.devoxx4kids.com Greenfoot Workshop Bobby - Snake

2. www.devoxx4kids.com Greenfoot Development Environment based on the Java programming language. Mainly designed to ease the Java language learning Allow to easily create 2D games Greenfoot is freely available on Microsoft Windows, Mac OS X, and Linux. http://www.greenfoot.org/

3. www.devoxx4kids.com The Java language « Object Oriented » Language One of the World’s most used programming language Allow to develop applications running on multiple systems – Windows, Mac, Linux, Android, …

4. www.devoxx4kids.com « Object Oriented » Java applications are made of « Objects » Each Object is composed of two main parts: – A set of internal properties – its « behavior », the actions it can do

5. www.devoxx4kids.com Classes and Objects To describe an object, we will define a class. A class is a kind of « model » allowing to build the objects – We also say that the objects are « instances » of the class

6. www.devoxx4kids.com public class GameElement { private int x; private int y; public GameElement(int initX, int initY) { x = initX; y = initY; } public int getX() { return x; } public int getY() { return y; } public void move(int xMove, int yMove) { x = x + xMove; y = y + yMove; } A Java Class sample

7. www.devoxx4kids.com Bobby-Snake 7

8. www.devoxx4kids.com New scenario 8

9. www.devoxx4kids.com World creation 9

10. www.devoxx4kids.com Snake World 10

11. www.devoxx4kids.com SnakeWorld code 11

12. www.devoxx4kids.com Inspect World 12

13. www.devoxx4kids.com Change the code We will use blocks of 32x32 pixels The game size will be 25 x 20 blocks 13

14. www.devoxx4kids.com Create a Block 14

15. www.devoxx4kids.com Create the Border 15

16. www.devoxx4kids.com Coordinates 16 (0,0)(1,0)(2,0)… (24,0) (0,1)(1,1)(2,1)… (24,1) (0,2)(1,2)(2,2)… (24,2) ………… … (0,19)(1,19)(2,19)…(24,19)

17. www.devoxx4kids.com Display the borders 17

18. www.devoxx4kids.com for loops 18 for ( initialization ; test ; post-processing ) { body ; }

19. www.devoxx4kids.com The game borders 19

20. www.devoxx4kids.com Class SnakeBody 20

21. www.devoxx4kids.com SnakeWorld changes 21

22. www.devoxx4kids.com Movement 22

23. www.devoxx4kids.com If Statement 23

24. www.devoxx4kids.com Limit the Snake size 24

25. www.devoxx4kids.com Change of direction 25

26. www.devoxx4kids.com Manage collisions (1) 26

27. www.devoxx4kids.com Manage collisions (2) 27

28. www.devoxx4kids.com Add Apples (1) 28

29. www.devoxx4kids.com Add Apples (2) 29

30. www.devoxx4kids.com Collision with an apple 30

31. www.devoxx4kids.com Add sounds 31

32. www.devoxx4kids.com Congratulations! You have completed your first Greenfoot game! You can now start to add new features in your game or start creating new games ! 32