1. Primitive variables Android Club 2015

2. 2 types of variables: Primitive single value (starts with uppercase letter) Complex multiple value (starts with lowercase letter)

3. Primitive data type int (0, 5, 87) boolean (true/false) char (‘a’, ‘b’, ‘c’)

4. Primitive: declaration [DATA_TYPE] [NAME]; int amount; boolean isOpen; char grade;

5. Primitive: initialization [DATA_TYPE] [NAME] = [INITIAL VALUE] int amount = 5; boolean isOpen = true; char grade = ‘a’;

6. Primitive: practice Example: int myNum; myNum = 5; System.out.println(myNum); Do this for char and boolean

7. Primitive: practice 2 Example: int myNum = 5; System.out.println(myNum); Do this for char and boolean

8. Primitive: practice 3 Name: Joe Richard Score: 30 Grade: D Passed: false

9. Primitive: numeric Data TypeBitsMinimumMaximumExample byte8-1281271 short16-32 7683276710 int32-2 147 483 6482 147 483 64710 long64-9,22E+189,22E+18100L float322 -149 (2-2 -23 )·2 127 150.5f double642 -1074 (2-2 -52 )·2 1023 150.5d

10. Numeric: practice 6: byte, short, int, long, float, double A. Declare: int myInt; B. Initialize: myInt = 5; C. Print: System.out.println(myInt);

11. Convert numeric Upward – SAFE (byte -> double) Downward – UNSAFE (double -> byte)

12. Upward convert: example short myShort = 256; System.out.println("myShort:"+myShort); float myFloat = myShort; System.out.println("myFloat:"+myFloat);

13. Upward convert: practice Create one short: 256 Convert it to float Print result

14. Downward convert: example double myDouble = 25.99; System.out.println("myDouble:"+myDouble); int myInt = (int)myDouble; System.out.println("myFloat:"+myInt);

15. Downward convert: practice Declare and initialize double: 8888,88d Convert double to int Print result

16. Operators Assignment Equality Mathematical Conditional

17. Assigning operator = assign

18. = example int x = 60; x = 50; int y=40; x=y;

19. = practice Create x which equals to 100 Create y which equals to 200 Then x equals to y Print

20. Mathematical operators + add - minus * multiply / divide % reminder

21. + example int x = 60; int y=40; int z = x+y+10;

22. + practice Create x which equals to 100 Create y which equals to 200 Create z which is sum of x and y Print

23. ++ example int x = 5; x++;

24. ++ practice Create x which equals to 8 Increment it by 1 Print

25. - example int x = 60; int y=40; int z = x-y-10;

26. - practice Create x which equals to 100 Create y which equals to 200 Create z which is y minus x Print

27. -- example int x = 5; x--;

28. -- practice Create x which equals to 17 Decrement it by 1 Print

29. Prefix and postfix: ++-- int x = 5; System.out.println(++x); int y = 5; System.out.println(y++);

30. * example int x = 100; int y = 2; int z = x*y;

31. * practice Create x which equals to 100 Create y which equals to 2 Create z which is x multiplied by y Print

32. / example int x = 100; int y = 2; int z = x/y;

33. / practice Create x which equals to 100 Create y which equals to 2 Create z which is x divided by y Print

34. % example int x = 13; int y = x % 10;

35. % practice Create x which equals to 100 Create y which equals to reminder of 100 divided by 7 Print

36. =[SOME OPERATOR] =+ =- =* =/

37. Complex data type String (“Joe Richard”, “Android”) Date Any object

38. Comparing operators == equal (do not hesitate with = assign) != not equal > more than >= more or equals < less than <= less or equals instanceof

39. Comparing example int x = 5; int y = 9; if (x > y) { System.out.println("x more than y"); } else { System.out.println("x less than y"); }

40. Comparing: practice Create x = 100; Create y = 200; Find which is less

41. Conditional operators && AND || OR

42. && vs || true && true = true true && false = false true || true = true true || false = true

43. Complex: declaration [DATA_TYPE] [NAME]; String name; String title; Date today; Date expireDate;

44. Complex: initialization [DATA_TYPE] [NAME] = new [DATA_TYPE](PARAMETER); String title = new String(“Alchemist”); String title= “Alchemist”; String country = new String(“Australia”); Date today = new Date();

45. CRAZY CALCULATOR System.out.println("Enter x"); Scanner scanner = new Scanner(System.in); int x = scanner.nextInt(); System.out.println("Enter y"); int y = scanner.nextInt(); System.out.println("x+y="+(x+y));

46. Homework: Update CC - + * / %

47. Questions? What did not you understand?

48. Review Chapter 4: Using Primitive Data Types

49. Thank you! Thank you for your attention!