Objective-C Awesomesauce!

Ruby and Objective-C seem like programming languages from two different worlds. When you take a closer look at them, you will start to see similarities. As a Ruby developer, I want to highlight these similarities in this talks and learn from what Objective-C does differently from Ruby.

Transcript

3. Ariejan de Vroom • @ariejan • http://ariejan.net
 Kabisa • @kabisaict • http://kabisa.nl
4. Ruby Ariejan de Vroom • @ariejan • http://ariejan.net
 Kabisa • @kabisaict • http://kabisa.nl
5. Objective-C Ariejan de Vroom • @ariejan • http://ariejan.net
 Kabisa • @kabisaict • http://kabisa.nl
6. … but why?
7. A Short History Of
 Programming Languages
8. The Influence of Smalltalk
9. #('a' 'b' 'c' ) do:[:each | Transcript show: each. Transcript cr. ].
10. Ruby Objective-C
11. Dynamically Typed
 Object Oriented
 Programming Languages
12. Dynamic Dispatching via Message Dispatching
13. @post.publish @post.send(:publish)
14. [post publish]; [post performSelector:@selector(publish)];
15. Objective-C is a Super Set of C
16. Objective-C is an Compiled Language
17. Objective-C has Forward Declarations
18. Objective-C has Macro’s
19. Objective-C has Pointers
20. Objective-C requires Manual Memory Management
21. Objective-C has Threading
22. Ruby is an Interpreted Language
23. Ruby has Duck-Typing
24. Ruby has No Pointers
25. Ruby does not require Manual Memory Management
26. Ruby does not require Manual Memory Management
27. Ruby has a Garbage Collector
28. Ruby has (broken) Threading
29. Objective-C Cocoa AppKit FoundationKit Cocoa Touch AppKit FoundationKit Mac OS X App iOS App Programming Stack
30. // ADVPerson.h ! #import <Foundation/Foundation.h> #import "ADVDepartment.h" ! @interface ADVPerson : NSObject { } ! @property (copy, nonatomic) NSString *name; @property (strong, nonatomic) ADVDepartment *department; @property (readonly, nonatomic) NSNumber *salary; ! + (ADVPerson *)personWithRandomData; ! - (void)giveRaiseOf:(NSNumber)amount withReason:(NSString *)reason; ! @end
31. // ADVPerson.h ! #import <Foundation/Foundation.h> #import "ADVDepartment.h" ! @interface ADVPerson : NSObject { } ! @property (copy, nonatomic) NSString *name; @property (strong, nonatomic) ADVDepartment *department; @property (readonly, nonatomic) NSNumber *salary; ! + (ADVPerson *)personWithRandomData; ! - (void)giveRaiseOf:(NSNumber)amount withReason:(NSString *)reason; ! @end
32. // ADVPerson.h ! #import <Foundation/Foundation.h> #import "ADVDepartment.h" ! @interface ADVPerson : NSObject { } ! @property (copy, nonatomic) NSString *name; @property (strong, nonatomic) ADVDepartment *department; @property (readonly, nonatomic) NSNumber *salary; ! + (ADVPerson *)personWithRandomData; ! - (void)giveRaiseOf:(NSNumber)amount withReason:(NSString *)reason; ! @end
33. // ADVPerson.h ! #import <Foundation/Foundation.h> #import "ADVDepartment.h" ! @interface ADVPerson : NSObject { } ! @property (copy, nonatomic) NSString *name; @property (strong, nonatomic) ADVDepartment *department; @property (readonly, nonatomic) NSNumber *salary; ! + (ADVPerson *)personWithRandomData; ! - (void)giveRaiseOf:(NSNumber)amount withReason:(NSString *)reason; ! @end
34. ADVPerson *person = [ADVPerson personWithRandomData]; [person giveRaiseOf:1000 withReason:@"For being awesome!"];
35. // ADVPerson.m ! #import "ADVPerson.h" ! @interface ADVPerson () @end ! @implementation ADVPerson ! + (ADVPerson *)personWithRandomData { ADVPerson *person = [[ADVPerson alloc] init]; [person setName:@"John Doe"]; [person setDepartment:[ADVDepartment randomDepartment]]; [person giveRaiseOf:2000 withReason:@"Initial salary"]; return person; } ! - (void)giveRaiseOf:(NSNumber)amount withReason:(NSString *)reason { _salary = _salary + amount; NSLog(@"Raising salary to %@ because %@", _salary, reason); } ! @end
36. // ADVPerson.m ! #import "ADVPerson.h" ! @interface ADVPerson () @end ! @implementation ADVPerson ! + (ADVPerson *)personWithRandomData { ADVPerson *person = [[ADVPerson alloc] init]; [person setName:@"John Doe"]; [person setDepartment:[ADVDepartment randomDepartment]]; [person giveRaiseOf:2000 withReason:@"Initial salary"]; return person; } ! - (void)giveRaiseOf:(NSNumber)amount withReason:(NSString *)reason { _salary = _salary + amount; NSLog(@"Raising salary to %@ because %@", _salary, reason); } ! @end
37. // ADVPerson.m ! #import "ADVPerson.h" ! @interface ADVPerson () - (void)setSalary:(NSNumber)amount; @end ! @implementation ADVPerson ! + (ADVPerson *)personWithRandomData { ADVPerson *person = [[ADVPerson alloc] init]; [person setName:@"John Doe"]; [person setDepartment:[ADVDepartment randomDepartment]]; [person giveRaiseOf:2000 withReason:@"Initial salary"]; return person; } ! - (void)giveRaiseOf:(NSNumber)amount withReason:(NSString *)reason { [self setSalary:(_salary + amount)]; NSLog(@"Raising salary to %@ because %@", _salary, reason); } ! @end
38. // NSString+Reverse.h @interface NSString (Reverse) { } - (NSString *)reverse; @end ! ! ! ! // NSString+Reverse.m @implementation NSString (Reverse) ! - (NSString *)reverse { // TODO: Implement this. } ! @end
39. Memory <ADVPerson name: “John Doe”> ADVPerson *john = [ADVPerson personWithRandomData]; ! NSLog(@"Person: %@", john.name); // Person: John Doe The Stack john
40. Memory <ADVPerson name: “John Doe”> ADVPerson *john = [ADVPerson personWithRandomData]; ! NSLog(@"Person: %@", john.name); // Person: John Doe ! ADVPerson *dick = john; The Stack john dick
41. Memory <ADVPerson name: “Dick Doe”> ADVPerson *john = [ADVPerson personWithRandomData]; ! NSLog(@"Person: %@", john.name); // Person: John Doe ! ADVPerson *dick = john; [dick setName:@"Dick Doe”]; The Stack john dick
42. Memory <ADVPerson name: “Dick Doe”> ADVPerson *john = [ADVPerson personWithRandomData]; ! NSLog(@"Person: %@", john.name); // Person: John Doe ! ADVPerson *dick = john; [dick setName:@"Dick Doe”]; ! NSLog(@"Person: %@", dick.name); // Person: Dick Doe The Stack john dick
43. Memory <ADVPerson name: “Dick Doe”> ADVPerson *john = [ADVPerson personWithRandomData]; ! NSLog(@"Person: %@", john.name); // Person: John Doe ! ADVPerson *dick = john; [dick setName:@"Dick Doe”]; ! NSLog(@"Person: %@", dick.name); // Person: Dick Doe ! NSLog(@"Person: %@", john.name); // Person: Dick Doe The Stack john dick
44. Mutable Immutable
45. NSCopying NSMutableCopying
46. Reference Counting
47. NSString *s = [[NSString alloc] init]; // Ref count is 1
48. NSString *s = [[NSString alloc] init]; // Ref count is 1 [s retain]; // Ref count is 2
49. NSString *s = [[NSString alloc] init]; // Ref count is 1 [s retain]; // Ref count is 2 [s release]; // Ref count is 1 again
50. NSString *s = [[NSString alloc] init]; // Ref count is 1 [s retain]; // Ref count is 2 [s release]; // Ref count is 1 again [s release]; // Ref count is 0
51. NSString *s = [[NSString alloc] init]; // Ref count is 1 [s retain]; // Ref count is 2 [s release]; // Ref count is 1 again [s release]; // Ref count is 0 s = nil; // Remove our pointer
52. NSString *s = [[NSString alloc] init]; // Ref count is 1 [s retain]; // Ref count is 2 [s release]; // Ref count is 1 again [s release]; // Ref count is 0 s = nil; // Remove our pointer ! ! NSString *s = [NSString stringWithString:@"Hello world"]; // Auto released! [s retain]; // To hang on to s
53. NSString *s = [[NSString alloc] init]; // Ref count is 1 [s retain]; // Ref count is 2 [s release]; // Ref count is 1 again [s release]; // Ref count is 0 s = nil; // Remove our pointer ! ! NSString *s = [NSString stringWithString:@"Hello world"]; // Auto released! [s retain]; // To hang on to s ! ! - (NSString *)helloWorldString { NSString *s = [[NSString alloc] initWithString:@"Hello world!"]; return [s autorelease]; }
54. ARC Automatic Reference Counting
55. @property (strong, nonatomic) ADVDepartment *department; @property (weak, nonatomic) ADVPeopleManager *peopleManager;
56. -fno-objc-arc
58. // ADVPriceFetcher.h #include <Foundation/Foundation.h> ! @interface ADVPriceFetcher : NSObject - (NSNumber *)fetchCurrentBitcoinPriceInEur; @end
59. // ADVPriceFetcher.h #include <Foundation/Foundation.h> ! @protocol ADVPriceFetcherDelegate - (void)fetchedCurrentBitcoinPriceInEur:(NSNumber *)price; @end ! @interface ADVPriceFetcher : NSObject - (void)fetchCurrentBitcoinPriceInEur; @end
60. // ADVPriceFetcher.h #include <Foundation/Foundation.h> ! @protocol ADVPriceFetcherDelegate - (void)fetchedCurrentBitcoinPriceInEur:(NSNumber *)price; @end ! @interface ADVPriceFetcher : NSObject @property (weak, nonatomic) id<ADVPriceFetcherDelegate> delegate; - (void)fetchCurrentBitcoinPriceInEur; @end
61. // ADVMainViewController.h #import "ADVPriceFetcher.h" ! @interface ADVMainViewController : UIViewController <ADVPriceFetcherDelegate> @property (strong, nonatomic) ADVPriceFetcher *priceFetcher; - (IBAction)pushRefreshButton; @end
62. // ADVMainViewController.m @implementation ADVMainViewController ! - (id)init { if ([super init]) { self.priceFetcher = [[ADVPriceFetcher alloc] init]; [self.priceFetcher setDelegate:self]; } return self; } ! - (IBAction)pushRefreshButton { [self.priceFetcher fetchCurrentBitcoinPriceInEur]; } ! - (void)fetchedCurrentBitcoinPriceInEur:(NSNumber *)price { NSLog(@"Fetch price: %@", price); } ! @end
63. // ADVPriceFetcher.m #import "ADVPriceFetch.h" ! @implementation ADVPriceFetcher ! - (void)fetchCurrentBitcoinPriceInEur { // Work our networking magic. NSNumber *price = /* ... */ if (_delegate && [_delegate respondsToSelector:@selector(fetchedCurrentBitcoinPriceInEur:)]) { [delegate fetchedCurrentBitcoinPriceInEur:price]; } } ! @end
64. @protocol ADVPriceFetcherDelegate - (void)fetchedCurrentBitcoinPriceInEur:(NSNumber *)price; ! @optional - (void)errorFetchingBitcoinPrice:(NSError *)error; ! @end
65. var fetcher = new ADVNetworkFetcher(); fetcher.fetchCurrentBitcoinPriceInEur({ success: function(price) { // … } });
66. - (IBAction)pushRefreshButton { [self.priceFetcher fetchCurrentBitcoinPriceInEur:^(NSNumber *price) { NSLog(@"Fetched price: %@", price) }]; }
67. // ADVPriceFetcher.h #include <Foundation/Foundation.h> @interface ADVPriceFetcher : NSObject - (void)fetchCurrentBitcoinPriceInEur:(void (^)(NSNumber *price)completed; @end ! ! // ADVPriceFetcher.m @implementation ADVPriceFetcher ! - (void)fetchCurrentBitcoinPriceInEur:(void (^)(NSNumber *price)completed { // Work our networking magic. NSNumber *price = /* ... */ completed(price); } @end
68. Grand Central Dispatch
69. NSNotificationCenter
70. Xcode
71. iTunes Connect
72. http://developer.apple.com
73. CocoaPods
74. I learned.
75. Mobile Design Is Really Hard™
76. Mobile ≠ Web
77. Think Different
78. I made an app.
79. Binary Deep http://aj.gs/binary-deep
80. Binary Deep http://aj.gs/binary-deep