Objective-C For Web Developers

Talk given at TechFest Northwest Arkansas 2012

Transcript

1. For Objective-C Web Developers Addam Hardy
2. @addamh this guy Ruby on Rails Javascript Developer iOS
4. web developer? it’s time to evolve
5. tablet sales to surpass desktop sales by 2015
6. demand supply
7. demand supply profit
9. the run down
10. strict superset of C Objective-C
11. strict superset of C compiled language Objective-C
12. strict superset of C compiled language object-oriented Objective-C
13. strict superset of C compiled language object-oriented dynamic Objective-C
14. strict superset of C compiled language object-oriented dynamic strictly typed Objective-C
15. strict superset of C compiled language object-oriented dynamic strictly typed smalltalk style messaging Objective-C
16. strict superset of C compiled language object-oriented dynamic strictly typed smalltalk style messaging very verbose Objective-C
17. difficulties for web developers
18. C bummers
19. C compiling! so much time! bummers
20. C compiling! so much time! the dynamic-ness. sort of. bummers
21. C compiling! so much time! the dynamic-ness. sort of. asynchronous/threading bummers
22. C compiling! so much time! the dynamic-ness. sort of. asynchronous/threading memory management bummers
23. C compiling! so much time! the dynamic-ness. sort of. asynchronous/threading memory management bummers
24. C compiling! so much time! the dynamic-ness. sort of. asynchronous/threading memory management static typing bummers
25. C compiling! so much time! the dynamic-ness. sort of. asynchronous/threading memory management static typing errors bummers
26. xcode
27. xcode
28. xcode
29. xcode
30. xcode
31. xcode
32. xcode
33. xcode
34. typing
35. typing Ruby PHP Objective-C $var = 21; $variable = “This is a string”; var = 21 variable = “This is a string” (int) var = 21; NSString *variable = @“This is a string”;
36. typing C Primitives Common Classes char short long unsigned char unsigned int int float double bool NSString NSNumber NSArray NSDictionary NSMutableArray NSMutableDictionary UIView UIButton id and 20,000 others..
37. header files implementation files wat?
38. headers / implementation class.h The public API for the class @interface Student { NSNumber *age; NSString *name; } @end
39. headers / implementation class.h class.m The public API for the class The instructions for the class @interface Student { NSNumber *age; NSString *name; } @end @implementation Student - (NSString *) name { } @end
40. creating classes
41. classes Ruby PHP class HelloWorld { // instance variables go here // methods go here public function sayHI() { print("Hello World!”); } } class HelloWorld // instance variables go here // methods go here def sayHI puts "Hello World!” end end
42. classes Objective-C @interface HelloWorld { NSString *statement = @”This is a string” } -(void) sayHI; @end
43. classes Ruby PHP class cat extends animal { public function be_cute() { print("I am teh cute”); } } class cat < animal def be_cute puts "I am teh cute” end end
44. classes Objective-C @interface Cat : Animal <CuteMultipler> { } -(void) beCute; @end
45. properties
46. properties @property (nonatomic, retain) NSString *title; @property (nonatomic, assign) int number;
47. properties @synthesize title; @synthesize number; [object setTitle:@”This is my title”]; NSLog(@”%@”, [object title]);
48. object instantiation
49. object instantiation Ruby PHP include_once('HelloWorld.class.php'); $hw = new HelloWorld; $hw->sayHI; require ‘HelloWorld’ hw = HelloWorld.new hw.sayHI
50. Objective-C #import <Foundation/Foundation.h> @interface HelloWorld : NSObject { } - (void)sayHI; @end object instantiation header
51. Objective-C #import “HelloWorld.h” @implementation HelloWorld - (void)sayHI { NSLog(@”Hi.”); } @end object instantiation header
52. Objective-C #import <Foundation/Foundation.h> #import "HelloWorld.h" int main (int argc, const char * argv[]) { HelloWorld *hw = [[HelloWorld alloc] init]; [hw printHelloDate]; return 0; } object instantiation main.m
53. methods /selectors
54. methods / selectors Ruby PHP function buyItem(item) { $cart = new ShoppingCart; $cart->purchase(item); } def buyItem(item) cart = ShoppingCart.new cart.purchase(item) end
55. Objective-C - (void)buyItem:(ItemObject*)item { ShoppingCart *cart = [[ShoppingCart alloc] init]; [cart purchase:item]; } methods / selectors
56. def addObserver(key_path, options, context) end methods / selectors
57. def addObserver(key_path, options, context) end methods / selectors addObserver(key_path, options, context)
58. -(void) addObserverForKeyPath:(NSIndexPath*)indexPath WithOptions:(NSDictionary*)options AndContext:(void*) { } methods / selectors
59. -(void) addObserverForKeyPath:(NSIndexPath*)indexPath WithOptions:(NSDictionary*)options AndContext:(void*) { } methods / selectors [object addObserverForKeyPath:indexPath WithOptions:options AndContext:nil]
60. common pitfalls
61. common pitfalls NSString *this = @”kitty”; NSString *that = @”kitty”; if(this == that){ NSLog(@”This will not happen”); } if([this isEqualToString:that]){ NSLog(@”This will happen!”); } NO YES
62. common pitfalls @synthesize this; @synthesize that; @synthesize those; @synthesize this, that, those; NO YES
63. common pitfalls @interface MyNewClass @end @interface MyNewClass : NSObject @end NO YES
64. common pitfalls start writing implementation right away always declare methods in header first then implement NO YES
65. just do it!
66. thanks!