Oct 20, 2018 iPlayground@NTU

1. Mixing ObjC, Swift and Japan
Tina Chang
LINE Fukuoka

2. INTRODUCTION
旅⽇日台灣⼯工程師
吃貨 🥞
iOS歷3年年 🐣
RUN FOR EAT

3. ‣ MIXING OVERVIEW
‣ CIRCULAR REFERENCE
‣ JAPAN

4. ‣ JAPAN
‣ MIXING OVERVIEW
‣ CIRCULAR REFERENCE
#

5. JAPAN ENGINEER SALARY?

6. AMAZON / GOOGLE / INDEED
TIER1
850万円↑

7. LINE / MERCARI / RAKUTEN
TIER2
600-900万円

8. OTHERS
400-700万円

9. HOW MUCH YOU CAN SAVE?

10. ✓ 所得稅
✓ 健康保險料
✓ 厚⽣生年年⾦金金保險

11. 薪⽔水900万円↓
80%

12. 薪⽔水900万円↑
70%

13. ✓ 房租
✓ ⽔水電瓦斯費
✓ 飲食費
✓ 交通費

14. ✓ 房租
✓ ⽔水電瓦斯費
✓ 飲食費
✓ 交通費
8万円
1万円
6万円
0円
15万円

15. ✓ 房租
✓ ⽔水電瓦斯費
✓ 飲食費
✓ 交通費
8万円
1万円
6万円
0円
15万円

16. 2000円
420円
780円
680円

17. 1000円
180円
430円
400円

18. ✓ 房租
✓ ⽔水電瓦斯費
✓ 飲食費
✓ 交通費
8万円
1万円
6万円
0円
15万円

19. 薪⽔水
600万円

20. 600万円 x 80% - 15万 x 12
300万円

21. ‣ JAPAN
‣ MIXING OVERVIEW
‣ CIRCULAR REFERENCE
#

22. GOOD POINTS FOR MIXING?

23. WE CAN WRITE SWIFT

24. Bridging
Header
Generated
Header

25. Bridging
Header
Generated
Header
Swift → Objective-C

26. Bridging
Header
Generated
Header
Objective-C → Swift

27. Bridging
Header
Generated
Header
Swift → Objective-CObjective-C → Swift
Mixed-Proj
Mixed-Proj-Bridging-Header.h Mixed_Proj-Swift.h

28. Swift → Objective-C

29. @objc (LINESticker)
class Sticker: NSObject {
}
// StickerViewController.m
- (instancetype)initWithSticker:(LINESticker*)sticker
{
self = [super init];
if (self) {
_sticker = sticker;
}
return self;
}
Swift
Objective-C
Swift → Objective-C

30. @objc (LINESticker)
class Sticker: NSObject {
}
// StickerViewController.m
#import “Mixed_Proj-Swift.h”
- (instancetype)initWithSticker:(LINESticker*)sticker
{
self = [super init];
if (self) {
_sticker = sticker;
}
return self;
}
Swift
Objective-C
Swift → Objective-C

31. Objective-C → Swift

32. class StickerListViewController: UIViewController {
func presentStickerViewController() {
let stickerViewController = StickerViewController()
present(stickerInfoViewController, animated: true, completion: nil)
}
}
// StickerViewController.h
@interface StickerViewController : UIViewController
@property (nonatomic, strong, nonnull) LINESticker *sticker;
@end
Swift
Objective-C
Objective-C → Swift

33. class StickerListViewController: UIViewController {
func presentStickerViewController() {
let stickerViewController = StickerViewController()
present(stickerInfoViewController, animated: true, completion: nil)
}
}
// StickerViewController.h
@interface StickerViewController : UIViewController
@end
Swift
Objective-C
Objective-C → Swift
// Mixed_Proj-Bridging-Header.h
#import "StickerViewController.h"

34. Bridging
Header
Generated
Header
Swift → Objective-CObjective-C → Swift
Mixed-Proj
Mixed-Proj-Bridging-Header.h Mixed_Proj-Swift.h

35. ‣ JAPAN
‣ MIXING OVERVIEW
‣ CIRCULAR REFERENCE
#

36. @objc (LINESticker)
class Sticker: NSObject {
}
// Mixed_Proj-Bridging-Header.h
#import "StickerViewController.h"
// StickerViewController.h
#import “Mixed_Proj-Swift.h"
@interface StickerViewController : UIViewController
@property (nonatomic, strong, nonnull) LINESticker *sticker;
@end
Swift
Objective-C
CIRCULAR REFERENCE

37. @objc (LINESticker)
class Sticker: NSObject {
}
// Mixed_Proj-Bridging-Header.h
#import "StickerViewController.h"
// StickerViewController.h
#import “Mixed_Proj-Swift.h"
@interface StickerViewController : UIViewController
@property (nonatomic, strong, nonnull) LINESticker *sticker;
@end
Swift
Objective-C
‘Mixed_Proj-Swift.h’ file not found
CIRCULAR REFERENCE

38. ‣ compile Swift module
‣ precompile Bridging Header file (Mixed-Proj-Bridging-Header.h)
‣ compile Swift source files
‣ Generated Header file (Mixed_Proj-Swift.h)
‣ compile Objective-C source files
BUILD PROCESS

39. Bridging
Header
Generated
Header
‣ Swift module
‣ Bridging Header file
‣ Swift source files
‣ Generated Header file
‣ Objective-C source files

40. Bridging
Header
Generated
Header
// Mixed_Proj-Bridging-Header.h
#import "StickerViewController.h"
‣ Swift module
‣ Bridging Header file
‣ Swift source files
‣ Generated Header file
‣ Objective-C source files

41. Bridging
Header
Generated
Header
// Mixed_Proj-Bridging-Header.h
#import "StickerViewController.h"
// StickerViewController.h
#import “Mixed_Proj-Swift.h"
@interface StickerViewController : UIViewController
@property (nonatomic, strong, nonnull) LINESticker *sticker;
@end
‣ Swift module
‣ Bridging Header file
‣ Swift source files
‣ Generated Header file
‣ Objective-C source files

42. Bridging
Header
Generated
Header
‣ Swift module
‣ Bridging Header file
‣ Swift source files
‣ Generated Header file
‣ Objective-C source files
// Mixed_Proj-Bridging-Header.h
#import "StickerViewController.h"
// StickerViewController.h
#import “Mixed_Proj-Swift.h"
@interface StickerViewController : UIViewController
@property (nonatomic, strong, nonnull) LINESticker *sticker;
@end

43. Bridging
Header
Generated
Header
‣ Swift module
‣ Bridging Header file
‣ Swift source files
‣ Generated Header file
‣ Objective-C source files
// Mixed_Proj-Bridging-Header.h
#import "StickerViewController.h"
// StickerViewController.h
#import “Mixed_Proj-Swift.h"
@interface StickerViewController : UIViewController
@property (nonatomic, strong, nonnull) LINESticker *sticker;
@end
‘Mixed_Proj-Swift.h’ file not found

44. @objc (LINESticker)
class Sticker: NSObject {
}
// Mixed_Proj-Bridging-Header.h
#import "StickerViewController.h"
// StickerViewController.h
#import “Mixed_Proj-Swift.h"
@interface StickerViewController : UIViewController
@property (nonatomic, strong, nonnull) LINESticker *sticker;
@end
Swift
Objective-C
‘Mixed_Proj-Swift.h’ file not found
CIRCULAR REFERENCE

45. FORWARD DECLARATION
@objc (LINESticker)
class Sticker: NSObject {
}
// Mixed_Proj-Bridging-Header.h
#import "StickerViewController.h"
// StickerViewController.h
@class LINESticker;
@interface StickerViewController : UIViewController
@property (nonatomic, strong, nonnull) LINESticker *sticker;
@end
Swift
Objective-C

46. HOW ABOUT PROTOCOL?

48. @objc (LINEProduct)
protocol Product: NSObjectProtocol {
}
// Mixed_Proj-Bridging-Header.h
#import "ProductViewController.h"
// ProductViewController.h
@protocol LINEProduct;
@interface ProductViewController : UIViewController
@property (nonatomic, strong, nonnull) id<LINEProduct> product;
@end
Swift
Objective-C
CIRCULAR REFERENCE - PROTOCOL

49. CONFORM PROTOCOL?

50. @objc (LINEProduct)
protocol Product: NSObjectProtocol {
}
// Mixed_Proj-Bridging-Header.h
#import “Theme.h”
// Theme.h
@protocol LINEProduct;
@interface Theme : NSObject <LINEProduct>
@end
Swift
Objective-C
CONFORM PROTOCOL

51. @objc (LINEProduct)
protocol Product: NSObjectProtocol {
}
// Mixed_Proj-Bridging-Header.h
#import “Theme.h”
// Theme.h
@protocol LINEProduct;
@interface Theme : NSObject <LINEProduct>
@end
Swift
Objective-C
Cannot find protocol definition for 'LINEProduct'
CONFORM PROTOCOL

52. SOLUTION
✓ REWRITE PROTOCOLS IN OBJC
✓ RETURN SELF AS PROTOCOL TYPE

53. // Theme.h
@protocol LINEProduct;
@interface Theme : NSObject
- (id<LINEProduct>)theme;
@end
Objective-C
// Theme.m
#import "Theme.h"
#import “Mixed_Proj-Swift.h”
@interface Theme() <LINEProduct>
@end
@implementation Theme
- (id<LINEProduct>)theme
{
return self;
}
@end
CONFORM PROTOCOL

54. Swift class used in ObjC class used in Swift

56. @objc (LINESticker)
class Sticker: NSObject {
}
// Mixed_Proj-Bridging-Header.h
#import "StickerViewController.h"
// StickerViewController.h
@class LINESticker;
@interface StickerViewController : UIViewController
@property (nonatomic, strong, nonnull) LINESticker *sticker;
@end
Swift
Objective-C
SWIFT→OBJC→SWIFT

57. class StickerListViewController: UIViewController {
func presentStickerViewController() {
let stickerViewController = StickerViewController()
stickerViewController.sticker = Sticker()
present(stickerViewController, animated: true, completion: nil)
}
}
SWIFT→OBJC→SWIFT

58. class StickerListViewController: UIViewController {
func presentStickerViewController() {
let stickerViewController = StickerViewController()
stickerViewController.sticker = Sticker()
present(stickerViewController, animated: true, completion: nil)
}
}
Value of type 'StickerViewController' has no member 'sticker'
SWIFT→OBJC→SWIFT

59. @objc (LINESticker)
class Sticker: NSObject {
}
// Mix_Proj-Swift.h
SWIFT_CLASS_NAMED("Sticker")
@interface LINESticker : NSObject
- (nonnull instancetype)init OBJC_DESIGNATED_INITIALIZER;
@end
Swift
Objective-C
SWIFT→OBJC→SWIFT

60. Swift
Objective-C
SWIFT→OBJC→SWIFT
func presentStickerViewController() {
let stickerViewController = StickerViewController()
stickerViewController.sticker = Sticker()
present(stickerViewController, animated: true, completion: nil)
}
// StickerViewController.h
@class LINESticker;
@interface StickerViewController : UIViewController
@property (nonatomic, strong, nonnull) LINESticker *sticker;
@end
?

61. SOLUTION
✓ DO NOT RENAME
✓ TYPEALIAS
@objc class Sticker: NSObject {
}
typealias Sticker = LINESticker
@objc class LINESticker: NSObject {
}

62. SWIFT→OBJC
‣ forward declaration in ObjC header
‣ rewrite Protocols in ObjC when conforming
‣ - (id<LINEProduct>)theme;
SWIFT→OBJC→SWIFT
‣ typealias
RECAP

63. ANY QUESTIONS?

64. welcomepig
welcomepig@gmail.com
WE ARE HIRING

65. THANK YOU $$$