The document discusses RxSwift, which is a library for reactive programming with Swift. It combines ReactiveX with Swift by providing Observables and Observers. Observables allow data streams to be observed and manipulated through operators like map, filter, etc. The document provides examples of using RxSwift to validate a password field by observing text changes and mapping valid/invalid states to display feedback. It also shows an example of observing a nickname field to call an API on valid input. Overall, the document introduces the key concepts of RxSwift like Observables, Observers, operators, and provides examples of validating user input fields reactively.

1. RxSwift
(github.com/devxoul)

2. • StyleShare Inc.
• SW Maestro 2
• RxSwift

3. RxSwift?

4. RxSwift = ReactiveX + Swift

5. RxSwift = ReactiveX + Swift

6. RxSwift = ReactiveX + Swift
?

7. RxSwift = ReactiveX + Swift
Re + ActiveX

10. RxSwift = ReactiveX + Swift
Reactive + Extension

11. RxSwift = ReactiveX + Swift

12. RxSwift = ReactiveX + Swift
?

13. a = 10
b = a * 2

14. a = 10
b = a * 2
print(b)

15. a = 10
b = a * 2
print(b) // 20

16. a = 10
b = a * 2
print(b) // 20
a = 30

17. a = 10
b = a * 2
print(b) // 20
a = 30
print(b)

18. a = 10
b = a * 2
print(b) // 20
a = 30
print(b) // 20

19. a = 10
b = a * 2
print(b) // 20
a = 30
print(b) // 20 60

20. ReactiveX
Observer
Pattern
Iterator
Pattern
Functional
Programming

21. ReactiveX
Observer
Pattern
Iterator
Pattern
Functional
Programming

22. Observable
Observer

23. Observable
Observer
observe

24. Observable
Observer
observe notify

25. Observable
ObserverObserver Observer

26. ReactiveX
Observer
Pattern
Iterator
Pattern
Functional
Programming

27. Iterator next()
hasNext()

28. Iterator next()
hasNext()
10 20 30 40

29. Iterator next()
hasNext()
10 20 30 40

30. Iterator next()
hasNext()
10 20 30 40
iterator.next()

31. Iterator next()
hasNext()
10 20 30 40
iterator.next() // 10

32. Iterator next()
hasNext()
10 20 30 40

33. Iterator next()
hasNext()
10 20 30 40
iterator.next()

34. Iterator next()
hasNext()
10 20 30 40
iterator.next() // 20

35. Iterator next()
hasNext()
10 20 30 40

36. Iterator next()
hasNext()
10 20 30 40
iterator.next()

37. Iterator next()
hasNext()
10 20 30 40
iterator.next() // 30

38. Iterator next()
hasNext()
10 20 30 40

39. Iterator next()
hasNext()
10 20 30 40
iterator.next()

40. Iterator next()
hasNext()
10 20 30 40
iterator.next() // 40

41. Iterator next()
hasNext()
10 20 30 40

42. Iterator next()
hasNext()
10 20 30 40
iterator.hasNext() // false

43. ReactiveX
Observer
Pattern
Iterator
Pattern
Functional
Programming

44. •
• ,

45. •
•
• ...
higher-order fuction
pure fuction

46. •
•
• ...
higher-order fuction
pure fuction

47. 1.
2.

48. var array = [2, 6, 3, 1, 7]
array.sort(by: { a, b in
return a < b
})

49. var array = [2, 6, 3, 1, 7]
array.sort(by: { a, b in
return a < b
})

50. var array = [2, 6, 3, 1, 7]
array.sort(by: { a, b in
return a < b
})

51. •
•
• ...
higher-order fuction
pure fuction

52. •
•

53. •
•
( , , I/O )

54. •
•

55. var rate = 1130
func krw(usd: Int) -> Int {
return usd * rate
}

56. var rate = 1130
func krw(usd: Int) -> Int {
return usd * rate
}
krw(usd: 2) // 2260
krw(usd: 3) // 3390

57. var rate = 1130
func krw(usd: Int) -> Int {
return usd * rate
}
rate = 1140
krw(usd: 2) // 2260
krw(usd: 3) // 3390

58. var rate = 1130
func krw(usd: Int) -> Int {
return usd * rate
}
rate = 1140
krw(usd: 2) // 2260 2280
krw(usd: 3) // 3390 3420

59. var rate = 1130
func krw(usd: Int) -> Int {
return usd * rate
}
rate = 1140
krw(usd: 2) // 2260 2280
krw(usd: 3) // 3390 3420

60. var rate = 1130
func krw(usd: Int) -> Int {
return usd * rate
}
rate = 1140
krw(usd: 2) // 2260 2280
krw(usd: 3) // 3390 3420

61. func krw(usd: Int) -> Int {
return usd * rate
}

62. func krw(usd: Int ) -> Int {
return usd * rate
}

63. func krw(usd: Int, rate: Int) -> Int {
return usd * rate
}

64. func krw(usd: Int, rate: Int) -> Int {
return usd * rate
}

65. ReactiveX
Observable
Pattern
Iterator
Pattern
Functional
Programming

67. a 10
b a * 2

68. a 10
b 20

73. a
b

74. 10 20 30 40a
20 40 60 80b

75. 10 20 30 40a
20 40 60 80b

76. 10 20 30 40a
20 40 60 80b
map(x => x * 2)

77. 10 20 30 40a
20 40 60 80b
map(x => x * 2)
Marble Diagrams

78. 20 40 60 80b
map(x => x * 2)
Observable.from([10, 20, 30, 40])

79. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }

80. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value)
})

81. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value)
})

82. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value)
})

83. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value) // 20
})

84. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value)
})

85. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value)
})

86. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value) // 40
})

87. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value)
})

88. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value)
})

89. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value) // 60
})

90. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value)
})

91. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value)
})

92. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value) // 80
})

93. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value) // 80
})
Observable

94. Observable.from([10, 20, 30, 40])
.map { $0 * 2 }
.subscribe(onNext: { value in
print(value) // 80
})
Observer

95. Password
(4 )

96. 1
(4 )
. ❌

97. 12
(4 )
. ❌

98. 123
(4 )
. ❌

99. 1234
(4 )
. 👍

101. "1"

102. "1"
map(str => str.length >= 4)

103. "1"
map(str => str.length >= 4)
false

104. "1"
false
map(str => str.length >= 4)
map(valid => getMessage(valid))

105. "1"
false
map(str => str.length >= 4)
"❌ "
map(valid => getMessage(valid))

106. "1" "12"
false
map(str => str.length >= 4)
"❌ "
map(valid => getMessage(valid))

107. "1" "12"
false false
map(str => str.length >= 4)
"❌ "
map(valid => getMessage(valid))

108. "1" "12"
false false
map(str => str.length >= 4)
"❌ " "❌ "
map(valid => getMessage(valid))

109. "1" "12" "123"
false false
map(str => str.length >= 4)
"❌ " "❌ "
map(valid => getMessage(valid))

110. "1" "12" "123"
false false false
map(str => str.length >= 4)
"❌ " "❌ "
map(valid => getMessage(valid))

111. "1" "12" "123"
false false false
map(str => str.length >= 4)
"❌ " "❌ " "❌ "
map(valid => getMessage(valid))

112. "1" "12" "123" "1234"
false false false
map(str => str.length >= 4)
"❌ " "❌ " "❌ "
map(valid => getMessage(valid))

113. "1" "12" "123" "1234"
false false false true
map(str => str.length >= 4)
"❌ " "❌ " "❌ "
map(valid => getMessage(valid))

114. false false false true
map(str => str.length >= 4)
map(valid => getMessage(valid))
"1" "12" "123" "1234"
"❌ " "❌ " "❌ " "👍"

115. passwordField.rx.text.orEmpty

116. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }

117. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
}

118. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}

119. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})

120. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})
"1"

121. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})
false

122. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})

123. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})

124. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})
"12"

125. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})
false

126. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})

127. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})

128. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})
"123"

129. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})
false

130. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})

131. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})

132. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})
"1234"

133. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})
true

134. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})

135. passwordField.rx.text.orEmpty
.map { $0.characters.count >= 4 }
.map { isValid in
if isValid {
return " . 👍"
} else {
return " . ❌"
}
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.rx.text = message
})

137. : Observable<String>
: Observable<Int>
: Observable<Void>
: Observable<CGPoint>
...

138. Observable

139. "1" "12" "123" "1234"

140. "1"

141. "1"

142. "1" "12"

143. "1" "12"

144. "1" "12" "123"

145. "1" "12" "123"

146. "1" "12" "123" "1234"

147. Nickname

148. . ❌

149. . ❌

150. . 👍

151. API

152. API
=

153. nicknameField.rx.text.orEmpty

154. nicknameField.rx.text.orEmpty
.map { nickname -> Bool in
// return true of false
}

155. 🤔 ?
nicknameField.rx.text.orEmpty
.map { nickname -> Bool in
// return true of false
}

156. nicknameField.rx.text.orEmpty
. map { nickname -> Bool in
}

157. nicknameField.rx.text.orEmpty
.flatMap { nickname -> Observable<Bool> in
}

158. nicknameField.rx.text.orEmpty
.flatMap { nickname -> Observable<Bool> in
return API.checkNickname(nickname)
}

159. nicknameField.rx.text.orEmpty
.flatMap { nickname -> Observable<Bool> in
return API.checkNickname(nickname)
}
.map { isAvailable in
return getMessage(isAvailable)
}

160. nicknameField.rx.text.orEmpty
.flatMap { nickname -> Observable<Bool> in
return API.checkNickname(nickname)
}
.map { isAvailable in
return getMessage(isAvailable)
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.text = message
})

161. map() vs flatMap()
20 40 60 80
map(x => x * 2)
10 20 30 40

162. map() vs flatMap()
flatMap( => )

163. map() vs flatMap()
flatMap( => )

164. map() vs flatMap()
flatMap( => )

165. map() vs flatMap()
flatMap( => )

166. map() vs flatMap()
flatMap( => )

167. map() vs flatMap()
flatMap( => )

168. map() vs flatMap()
flatMap( => )

169. map() vs flatMap()
flatMap( => )

170. map() vs flatMap()
flatMap( => )

171. map() vs flatMap()
flatMap( => )

172. map() vs flatMap()
flatMap( => )

173. Nickname

174. checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")

175. nicknameField.rx.text.orEmpty
.flatMap { nickname -> Observable<Bool> in
return API.checkNickname(nickname)
}
.map { isAvailable in
return getMessage(isAvailable)
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.text = message
})

176. nicknameField.rx.text.orEmpty
.debounce(0.3, scheduler: MainScheduler.instance)
.flatMap { nickname -> Observable<Bool> in
return API.checkNickname(nickname)
}
.map { isAvailable in
return getMessage(isAvailable)
}
.subscribe(onNext: { [weak self] message in
self?.messageLabel.text = message
})

177. checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")

178. checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
0.3s
0.3s
0.3s

179. checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
checkNickname(" ")
0.3s
0.3s
0.3s

180. 1 4
debounce
1 2 3 4

182. , Observable

183. Timer
00:17

184. Timer
00:17
Observable<Int>
.interval(1, scheduler: ...)
.subscribe(onNext: { tick in
print(tick)
})

185. Timer
00:17

186. Start

187. 17
18
19
20
21
...
Start

188. Start
Observable

189. Timer
00:17
Observable<Int>
.interval(1, scheduler: ...)
.subscribe(onNext: { tick in
print(tick)
})

190. Timer
00:17
var disposeBag = DisposeBag()
Observable<Int>
.interval(1, scheduler: ...)
.subscribe(onNext: { tick in
print(tick)
})
.disposed(by: disposeBag)

191. Timer
00:17
var disposeBag = DisposeBag()
Observable<Int>
.interval(1, scheduler: ...)
.subscribe(onNext: { tick in
print(tick)
})
.disposed(by: disposeBag)

192. var disposeBag = DisposeBag()
Observable<Int>
.interval(1, scheduler: ...)
.subscribe(onNext: { tick in
print(tick)
})
.disposed(by: disposeBag)
Start

193. var disposeBag = DisposeBag()
Observable<Int>
.interval(1, scheduler: ...)
.subscribe(onNext: { tick in
print(tick)
})
.disposed(by: disposeBag)
Start

194. var disposeBag = DisposeBag()
Observable<Int>
.interval(1, scheduler: ...)
.subscribe(onNext: { tick in
print(tick)
})
.disposed(by: disposeBag)
Start

195. var disposeBag = DisposeBag()
Observable<Int>
.interval(1, scheduler: ...)
.subscribe(onNext: { tick in
print(tick)
})
.disposed(by: disposeBag)
Start
Dispose

196. •
•
•
RxSwift

197. http://reactivex.io
http://rxswift.org
http://community.rxswift.org
https://rxswift-slack.herokuapp.com

198. .
(github.com/devxoul)