Kotlin-Workshop Day #1

Android Academy TLV - Kotlin workshop

Co-created with
Eden Bugdary Machluf and Hadas Peled

Transcript

1. Kotlin Workshop by Hadas Peled Gil Goldzweig Eden Machluf 15/10/19 WIFI: Guest Password: BrokenWires@@2019
4. > 4,000 members Largest Android Active Community
5. What Do We Do? • Kotlin workshop • Fundamentals • Design • Hackathon • Advanced • Partner Events • Mentors Program
6. Coming soon.. Fundamentals course
7. What Do We Do? • Kotlin workshop • Fundamentals • Design • Hackathon • Advanced • Partner Events • Mentors Program
8. Mentors Alexey Korolev Alex Vainshtein Benny Pivnic David Harush Hezi Dimri Hazi Corly Ben Michaeli Avishay Peretz Andrey Lebedev Eugene Rozenberg David Vardi Lior Prigal Maya Gorel Michael Groenendijk Orit Malki Rebecca Hamelsdorf Ronen Sabag Regev Avraham Sergio Geralnik Yossi Rizgan Daniel Szasz
9. facebook.com/groups/android.academy.ils/
10. https://t.me/androidAcademyGlobal
11. Leading team
12. Gil Goldzweig Android tech lead @ 10bis Github Twitter
13. Hadas Peled Android Developer @ Register Now! 28.11.2019 . Microsoft Reactor Dubnov 7, Tel - Aviv
14. Eden Bugdary Machluf Android Developer @ Maternity leave Android Academy Leading Team Member
15. Schedule 17:00- 17:30 - lecture 17:30-18:00 - hands on 18:00-18:30- lecture 18:30-18:50 - hands on 18:50 - 19:00 - coffee break 19:00-19:30- lecture 19:30-20:00 - hands on 20:00-20:30- lecture 20:30-21:00 - hands on
17. Today syllabus ▢ Workspace ▢ Operators ▢ Variables ▢ Null safety ▢ Strings ▢ Conditions ▢ Arrays & loops ▢ Ranges ▢ Functions ▢ Classes
18. Today syllabus ▢ Workspace ▢ Kotlin basics ▢ Functions ▢ Classes
19. Workspace - playground https://play.kotlinlang.org
20. Workspace - playground https://play.kotlinlang.org
21. Workspace - Repl Tools-> Kotlin -> Kotlin REPL
22. Exercises Git with exercises
24. Basic operators • Common operators: ◦ + , - , * , / ◦ When we use Int the result will be Int and so on. println(2 * "Bye ") => Bye Bye ◦ Can be used with any type
25. Basic operators • For each operator we can use operation function. 2.times(3) == 2 * 3
26. How to declare a variable?
27. How to declare a variable? var language = "Kotlin" val score = 95
28. How to declare a variable? var language: String = "Kotlin" val score = 95
29. How to declare a variable? var language: String = "Kotlin" val score: Int = 95
30. How to declare a variable? var language = "Kotlin" val score = 95
31. Difference between var and val
32. Difference between var and val • val - Immutable reference - The variable cannot be changed once the value is assigned. It is similar to final variable in Java.
33. Difference between var and val • val - Immutable reference - The variable cannot be changed once the value is assigned. It is similar to final variable in Java. • var - Mutable reference - The variable can be changed later in the program. It corresponds to regular Java variable.
34. Difference between var and val • val - Immutable reference - The variable cannot be changed once the value is assigned. It is similar to final variable in Java. • var - Mutable reference - The variable can be changed later in the program. It corresponds to regular Java variable.
35. Kotlin Null Safety
37. Kotlin Null Safety Kotlin could never throw a NullPointerException.
38. Kotlin Null Safety Kotlin could never throw a NullPointerException... unless you ask for it.
39. Kotlin Null Safety Kotlin could never throw a NullPointerException... unless you* ask for it.
40. How to declare a nullable reference? Differentiate between nullable references and non-nullable references.
41. var b: String? = null How to declare a nullable reference? Differentiate between nullable references and non-nullable references.
42. var b: String? = null How to declare a nullable reference? Differentiate between nullable references and non-nullable references.
43. var b: String? = null How to declare a nullable reference? Differentiate between nullable references and non-nullable references.
44. var b: String? = null How to declare a nullable reference? Differentiate between nullable references and non-nullable references.
45. var b: String? = null How to declare a nullable reference? Differentiate between nullable references and non-nullable references.
46. var b: String = null How to declare a nullable reference? Differentiate between nullable references and non-nullable references.
47. var b: String = null How to declare a nullable reference? Differentiate between nullable references and non-nullable references.
48. Kotlin NullPointerException
49. Kotlin NullPointerException • When you ask for a NullPointerException explicitly • From Outside Kotlin • Data inconsistency
50. Kotlin NullPointerException • When you ask for a NullPointerException explicitly ◦ throw NullPointerException() ◦ Use !! operator. • From Outside Kotlin • Data inconsistency
51. Kotlin NullPointerException • When you ask for a NullPointerException explicitly ◦ throw NullPointerException() ◦ Use !! operator. • From Outside Kotlin • Data inconsistency
52. Use !! operator
53. Use !! operator var b: String? = null var bLength = b!!.length
54. Use !! operator var b: String? = null var bLength = b!!.length
55. Use !! operator var b: String? = null var bLength = b!!.length
56. Use !! operator var b: String? = null var bLength = b!!.length
57. Kotlin NullPointerException • When you ask for a NullPointerException explicitly ◦ throw NullPointerException() ◦ Use !! operator. • From Outside Kotlin • Data inconsistency
58. Kotlin NullPointerException • When you ask for a NullPointerException explicitly ◦ throw NullPointerException() ◦ Use !! operator. • From Outside Kotlin • Data inconsistency
60. How Kotlin handles Null Safety ? • Differentiate between nullable references and non-nullable references. • User explicitly checks for a null in conditions • Using a Safe Call Operator ?. • Elvis Operator ?: : If reference to a val is not null, use the value, else use some default value that is not null
61. How Kotlin handles Null Safety ? • Differentiate between nullable references and non-nullable references. • User explicitly checks for a null in conditions • Using a Safe Call Operator ?. • Elvis Operator ?: : If reference to a val is not null, use the value, else use some default value that is not null
62. User explicitly checks for a null in conditions
63. User explicitly checks for a null in conditions if(b != null) { //b is not null!! }
64. User explicitly checks for a null in conditions if(b != null) { //b is not null!! }
65. How Kotlin handles Null Safety ? • Differentiate between nullable references and non-nullable references. • User explicitly checks for a null in conditions • Using a Safe Call Operator ?. • Elvis Operator ?: : If reference to a val is not null, use the value, else use some default value that is not null
66. Using Safe Call Operator val b: String? = null val bLength = b?.length
67. Using Safe Call Operator val b: String? = null val bLength = b?.length
68. Using Safe Call Operator val b: String? = null val bLength = b?.length
69. Using Safe Call Operator val b: String? = null val bLength = b?.length
70. Using Safe Call Operator val b: String? = null val bLength: Int? = b?.length
71. Using Safe Call Operator
72. Using Safe Call Operator val canDo: CanDo? = null canDo?.doStuffThatMatters()
73. Using Safe Call Operator val canDo: CanDo? = null canDo?.doStuffThatMatters()
74. Using Safe Call Operator val canDo: CanDo? = null canDo?.doStuffThatMatters()
75. Using Safe Call Operator val canDo: CanDo? = null canDo?.doStuffThatMatters()
76. Using Safe Call Operator val canDo: CanDo? = null canDo?.doStuffThatMatters()
77. How Kotlin handles Null Safety ? • Differentiate between nullable references and non-nullable references. • User explicitly checks for a null in conditions • Using a Safe Call Operator ?. • Elvis Operator ?: : If reference to a variable is not null, use the value, else use some default value that is not null
78. How Kotlin handles Null Safety ?
79. Elvis Operator val b: String? = null val bLength: Int? = b?.length
80. Elvis Operator val b: String? = null val bLength: Int? = b?.length
81. Elvis Operator val b: String? = null val bLength: Int? = b?.length
82. Elvis Operator val b: String? = null val bLength: Int? = b?.length
83. Elvis Operator val b: String? = null val bLength: Int? = b?.length
84. Elvis Operator val b: String? = null val bLength: Int = b?.length // ERROR - Type mismatch: inferred type is Int? but Int was // expected
85. Elvis Operator val b: String? = null val bLength: Int = b?.length ?: 0
86. Elvis Operator val b: String? = null val bLength: Int = b?.length ?: 0
87. Elvis Operator val b: String? = null val bLength: Int = b?.length ?: 0
88. String templates
89. String templates val math = 100 val english = 90
90. String templates val math = 100 val english = 90 val diploma = "math: " + math + "\nenglish: " + english
91. String templates val math = 100 val english = 90 val diploma = "math: " + math + "\nenglish: " + english math: 100 english: 90
92. String templates val math = 100 val english = 90 val diploma = "math: $math \nenglish: $english" math: 100 english: 90
93. String templates val math = 100 val english = 90 val diploma = "math: $math \nenglish: $english" math: 100 english: 90
94. String templates val math = 100 val english = 90 val diploma = "math: $math \nenglish: $english" math: 100 english: 90
95. String templates val math = 100 val english = 90 val diploma = "math: $math \nenglish: $english" val average = "average: ${(math + english) / 2}"
96. String templates val math = 100 val english = 90 val diploma = "math: $math \nenglish: $english" val average = "average: ${(math + english) / 2}"
97. String templates val math = 100 val english = 90 val diploma = "math: $math \nenglish: $english" val average = "average: ${(math + english) / 2}"
98. String templates val math = 100 val english = 90 val diploma = "math: $math \nenglish: $english" val average = "average: ${(math + english) / 2}" average: 95
99. WORKSHOP!!!
100. Control Flow
101. If // With else var max: Int if (a > b) { max = a } else { max = b }
102. If // With else var max: Int if (a > b) { max = a } else { max = b }
103. If // With else var max: Int if (a > b) { max = a } else { max = b }
104. If // With else var max: Int if (a > b) { max = a } else { max = b }
105. If // With else var max: Int if (a > b) { max = a } else { max = b }
106. If // With else var max: Int if (a > b) { max = a } else { max = b }
107. If // With else var max: Int if (a > b) { max = a } else { max = b } // Traditional usage var max = a if (max < b) max = b
108. If // With else var max: Int if (a > b) { max = a } else { max = b } // Traditional usage var max = a if (max < b) max = b
109. If // With else var max: Int if (a > b) { max = a } else { max = b } // Traditional usage var max = a if (max < b) max = b
110. If // With else var max: Int if (a > b) { max = a } else { max = b } // Traditional usage var max = a if (max < b) max = b
111. When
112. When when (x) { 1 -> print("x == 1") 2 -> print("x == 2") else -> { // Note the block print("x is neither 1 nor 2") } }
113. When when (x) { 1 -> print("x == 1") 2 -> print("x == 2") else -> { // Note the block print("x is neither 1 nor 2") } }
114. When when (x) { 1 -> print("x == 1") 2 -> print("x == 2") else -> { // Note the block print("x is neither 1 nor 2") } }
115. When when (x) { 1 -> print("x == 1") 2 -> print("x == 2") else -> { // Note the block print("x is neither 1 nor 2") } }
116. When when (x) { 1 -> print("x == 1") 2 -> print("x == 2") else -> { // Note the block print("x is neither 1 nor 2") } }
117. When when (x) { 1 -> print("x == 1") 2 -> print("x == 2") else -> { // Note the block print("x is neither 1 nor 2") } }
118. When when (x) { 1 -> print("x == 1") 2 -> print("x == 2") else -> { // Note the block print("x is neither 1 nor 2") } }
119. When when (x) { 1 -> print("x == 1") 2 -> print("x == 2") else -> { // Note the block print("x is neither 1 nor 2") } }
120. When when (x) { 1 -> print("x == 1") 2 -> print("x == 2") else -> { // Note the block print("x is neither 1 nor 2") } }
121. When when (x) { 1 -> print("x == $x") 2 -> print("x == $x") else -> { // Note the block print("x is neither 1 nor 2") } }
122. When when (x) { 1,2 -> print("x == $x") else -> { // Note the block print("x is neither 1 nor 2") } }
123. When when (x) { 1,2 -> print("x == $x") else -> { // Note the block print("x is neither 1 nor 2") } }
124. When
125. When when (x) { myFun(s) -> print("myFun(s) == x") else -> print("myFun(s) is not x") }
126. When when (x) { myFun(s) -> print("myFun(s) == x") else -> print("myFun(s) is not x") }
127. When when { x.isOdd() -> print("x is odd") s.isEven() -> print("s is even") else -> print("else") }
128. When when { x.isOdd() -> print("x is odd") s.isEven() -> print("s is even") else -> print("else") }
129. public class MyTest { @Test fun test() { var subject = TestSubject() subject.method() // dereference directly } }
130. public class MyTest { @Test fun test() { var subject = TestSubject() subject.method() // dereference directly } }
131. public class MyTest { var subject: TestSubject @SetUp fun setup() { subject = TestSubject() } @Test fun test() { subject.method() // dereference directly } }
132. public class MyTest { var subject: TestSubject @SetUp fun setup() { subject = TestSubject() } @Test fun test() { subject.method() // dereference directly } } ?
133. public class MyTest { var subject: TestSubject @SetUp fun setup() { subject = TestSubject() } @Test fun test() { subject.method() // dereference directly } } lateinit
134. Arrays
135. Typed arrays • Array of specific type val numbers = intArrayOf(10 , 20 , 30) => [10, 20 ,30] val chars = charArrayOf('1' , '2' , '3') => ['1' , '2' , '3'] val doubleNumbers = doubleArrayOf(1.0 , 2.5 , 3.0) => [1.0 , 2.5 , 3.0]
136. Typed arrays • Array of specific type val numbers = intArrayOf(10 , 20 , 30 , "Eden")
137. Untyped arrays val notOnlyNumbers = arrayOf(10 , 20 , 30 , "Eden")
138. Untyped arrays val notOnlyNumbers = arrayOf(10 , 20 , 30 , "Eden") =>[10 , 20 , 30 , "Eden"]
139. Arrays- dynamic init val squares = Array(5) { i -> (i * i).toString() }
140. Arrays- dynamic init val squares = Array(5) { i -> (i * i).toString() } size
141. Arrays- dynamic init val squares = Array(5) { i -> (i * i).toString() } Cell index (iterator)
142. Arrays- dynamic init val squares = Array(5) { i -> (i * i).toString() } Cell content
143. Arrays- dynamic init val squares = Array(5) { i -> (i * i).toString() } Casting to String
144. Arrays- dynamic init val squares = Array(5) { i -> (i * i).toString() } => ["0", "1", "4", "9", "16"]
145. For loops
146. For loops val names = arrayOf("Ori", "Shir", "Adi") for (name in names) { println(name) }
147. For loops val names = arrayOf("Ori", "Shir", "Adi") for (name in names) { println(name) }
148. For loops val names = arrayOf("Ori", "Shir", "Adi") for (name in names) { println(name) } Iterate read only variable
149. For loops val names = arrayOf("Ori", "Shir", "Adi") for (name in names) { println(name) } Iterable object
150. For loops val names = arrayOf("Ori", "Shir", "Adi") for (name in names) { println(name) }
151. For loops val names = arrayOf("Ori", "Shir", "Adi") for (name in names) { println(name) } //output Ori Shir Adi
152. For loops .with index for ((index, value) in names.withIndex()) { println("Cell #$index: name is $value") }
153. For loops .with index for ((index, value) in names.withIndex()) { println("Cell #$index: name is $value") }
154. For loops .with index for ((index, value) in names.withIndex()) { println("Cell #$index: name is $value") }
155. For loops .with index for ((index, value) in names.withIndex()) { println("Cell #$index: name is $value") }
156. For loops .with index for ((index, value) in names.withIndex()) { println("Cell #$index: name is $value") } => Cell #0: the name is Ori Cell #1: the name is Shir Cell #2: the name is Adi
157. Ranges
158. Ranges if (i >= 1 && i <= 4) { print("Valid") }
159. Ranges if (i >= 1 && i <= 4) { print("Valid") } for (int i = 1; i != 4; i++) { print(i) }
160. Ranges if (i in 1..4) { print("Valid") } for (int i = 1; i != 4; i++) { print(i) }
161. Ranges if (i in 1..4) { print("Valid") } for (i in 1..4) { print(i) // Outputs -> 1, 2, 3, 4 }
162. Ranges for (i in 1..8) print(i)
163. Ranges for (i in 1..8 step 2) print(i)
164. Ranges for (i in 1..8 step 2) print(i) // Outputs -> 1, 3, 5, 7
165. Ranges for (i in 1..8 step 2) print(i) // Outputs -> 1, 3, 5, 7 for (i in 8..1 step 2) print(i)
166. Ranges for (i in 1..8 step 2) print(i) // Outputs -> 1, 3, 5, 7 for (i in 8 downTo 1 step 2) print(i)
167. Ranges for (i in 1..8 step 2) print(i) // Outputs -> 1, 3, 5, 7 for (i in 8 downTo 1 step 2) print(i) // Outputs -> 8, 6, 4, 2
168. Ranges for (i in 1..8 step 2) print(i) // Outputs -> 1, 3, 5, 7 for (i in 8 downTo 1 step 2) print(i) // Outputs -> 8, 6, 4, 2 for (i in 0..array.length) { array[i] }
169. Ranges for (i in 1..8 step 2) print(i) // Outputs -> 1, 3, 5, 7 for (i in 8 downTo 1 step 2) print(i) // Outputs -> 8, 6, 4, 2 for (i in 0..array.length) { array[i] //Runtime exception IndexOutOfBounds }
170. Ranges for (i in 1..8 step 2) print(i) // Outputs -> 1, 3, 5, 7 for (i in 8 downTo 1 step 2) print(i) // Outputs -> 8, 6, 4, 2 for (i in 0..array.length - 1) { array[i] }
171. Ranges for (i in 1..8 step 2) print(i) // Outputs -> 1, 3, 5, 7 for (i in 8 downTo 1 step 2) print(i) // Outputs -> 8, 6, 4, 2 for (i in 0..array.length - 1) { array[i] //Everything works }
172. Ranges for (i in 1..8 step 2) print(i) // Outputs -> 1, 3, 5, 7 for (i in 8 downTo 1 step 2) print(i) // Outputs -> 8, 6, 4, 2 for (i in 0 until array.length) { array[i] //Everything works }
173. Ranges for (i in 1..8 step 2) print(i) // Outputs -> 1, 3, 5, 7 for (i in 8 downTo 1 step 2) print(i) // Outputs -> 8, 6, 4, 2 for (i in 0 until array.length) { array[i] //Everything works } for (i in 'a'..'c') print(i)
174. Ranges for (i in 1..8 step 2) print(i) // Outputs -> 1, 3, 5, 7 for (i in 8 downTo 1 step 2) print(i) // Outputs -> 8, 6, 4, 2 for (i in 0 until array.length) { array[i] //Everything works } for (i in 'a'..'c') print(i) // Outputs -> 'a', 'b', 'c'
175. Everything is an expressing
176. If expression val max = if (i in 1..4) i else 4
177. If expression val max = if (i in 1..4) { print("I is valid") i } else { print("I is not valid") 4 }
178. If expression val max = if (i in 1..4) { print("I is valid") i } else { print("I is not valid") 4 }
179. If expression val max = if (i in 1..4) { print("I is valid") i } else { print("I is not valid") 4 }
180. If expression val max = if (i in 1..4) { print("I is valid") i } else { print("I is not valid") 4 }
181. If expression val max = if (i in 1..4) { print("I is valid") i } else { print("I is not valid") 4 }
182. If expression val max = if (i in 1..4) { print("I is valid") i } else { print("I is not valid") 4 }
183. If expression val max = if (i in 1..4) { print("I is valid") i } else { print("I is not valid") 4 }
184. If expression
185. If expression val personHeight = "You're a ${if (person.isTall) "tall" else "short"} person"
186. when expression val isPretty = when (speaker) { "Gil Goldzweig" -> true "Hadas Peled" -> true "Eden Bugdary" -> true else -> false }
187. when expression val isPretty = when (speaker) { "Gil Goldzweig" -> { print("Speaker is awesome") true } "Hadas Peled" -> true "Eden Bugdary" -> true else -> false }
188. WORKSHOP!!!
189. Functions
190. Functions - main fun main(args: Array<String>) { println("Hello World!") }
191. Functions - main fun main() { println("Hello World!") }
192. Functions fun greeting(name: String): String { return "Hello " + name }
193. Functions fun greeting(name: String): String { return "Hello " + name }
194. Functions fun greeting(name: String): String { return "Hello " + name }
195. Functions fun greeting(name: String): String { return "Hello " + name }
196. Functions fun greeting(name: String): String { return "Hello " + name } Variable name
197. Functions fun greeting(name: String): String { return "Hello " + name } Variable type
198. Functions fun greeting(name: String): String { return "Hello " + name } Return value
199. Functions fun greeting(name: String) { return "Hello " + name }
200. Functions fun greeting(name: String) { // Returns -> Unit return "Hello " + name }
201. Functions - default values fun greeting(name: String): String { return "Hello " + name }
202. Functions - default values fun greeting(name: String = "Android"): String { return "Hello " + name } greeting() // Output -> Hello Android greeting("Gil") // Output -> Hello Gil
203. Functions - named arguments fun greeting(name: String): String { return "Hello " + name }
204. Functions - named arguments fun greeting(name: String, age: Int): String { return "Hello " + name }
205. Functions - named arguments fun greeting(name: String, age: Int): String { return "Hello " + name + "your age " + age }
206. Functions - named arguments fun greeting(name: String, age: Int): String { return "Hello " + name + "your age " + age } greeting("Gil", 19)
207. Functions - named arguments fun greeting(name: String, age: Int): String { return "Hello " + name + "your age " + age } greeting("Gil", 19) greeting(age = 19, name = "Gil")
208. Functions - named arguments fun greeting(name: String = "Gil", age: Int): String { return "Hello " + name + "your age " + age }
209. Functions - named arguments fun greeting(name: String = "Gil", age: Int): String { return "Hello " + name + "your age " + age } greeting(age = 19)
210. Functions - single line function fun greeting(name: String, age: Int): String { return "Hello " + name + "your age " + age }
211. Functions - single line function fun greeting(name: String, age: Int): String = "Hello " + name + "your age: " + age
212. Functions - single line function fun greeting(name: String, age: Int): String = "Hello " + name + "your age: " + age
213. Functions - single line function fun greeting(name: String, age: Int) = "Hello " + name + "your age: " + age
214. Functions - single line function fun greeting(name: String, age: Int) = "Hello $name your age: $age"
215. Filters
216. Filters someItems.filter{condition}
217. Filters someItems.filter{condition}
218. Filters someItems.filter{condition}
219. Filters - example val names = arrayOf("Ori", "Shir", "Adi", "Oren") println( names.filter {it[0] == 'O'} )
220. Filters - example val names = arrayOf("Ori", "Shir", "Adi", "Oren") println( names.filter {it[0] == 'O'} )
221. Filters - example val names = arrayOf("Ori", "Shir", "Adi", "Oren") println( names.filter {it[0] == 'O'} ) collection of items
222. Filters - example val names = arrayOf("Ori", "Shir", "Adi", "Oren") println( names.filter {it[0] == 'O'} )
223. Filters - example val names = arrayOf("Ori", "Shir", "Adi", "Oren") println( names.filter {it[0] == 'O'} ) condition
224. Filters - example val names = arrayOf("Ori", "Shir", "Adi", "Oren") println( names.filter {it[0] == 'O'} ) => [Ori, Oren]
225. Filters - Eager/Lazy • By default filter is eager. Everytime, the filter creates a new list of the elements that pass through the filter.
226. Filters - Eager val oNames = names.filter {it[0] == 'O'} println( oNames ) => [Ori, Oren]
227. Filters - Eager val oNames = names.filter {it[0] == 'O'} println( oNames ) => [Ori, Oren]
228. Filters - Eager val oNames = names.filter {it[0] == 'O'} println( oNames ) => [Ori, Oren]
229. Filters - Eager/Lazy What about lazy? • For lazy we can use a sequence. ◦ Sequence - a collection that can only look at one item at a time.
230. Filters - Lazy val sequenceONames = names.asSequence().filter {it[0] == 'O'} println( sequenceONames )
231. Filters - Lazy val sequenceONames = names.asSequence().filter {it[0] == 'O'} println( sequenceONames ) //
232. Filters - Lazy val sequenceONames = names.asSequence().filter {it[0] == 'O'} println( sequenceONames.toList() ) //[Ori, Oren]
233. Repeat fun
234. Repeat fun for (i in 1..5){ println("Hello ") } // Hello Hello Hello Hello Hello
235. Repeat fun • Executes the given function action specified number of times.
236. Repeat fun repeat(5) { println("Hello") }
237. Repeat fun repeat(5) { println("Hello") } times
238. Repeat fun repeat(5) { println("Hello") } action
239. Repeat fun repeat(5) { println("Hello") } // Hello Hello Hello Hello Hello
240. Lambdas
241. Lambdas
242. Lambdas { println( "Hello Android Academy" ) }()
243. Lambdas { println( "Hello Android Academy" ) }()
244. Lambdas { println( "Hello Android Academy" ) }()
245. Lambdas { println( "Hello Android Academy" ) }() => Hello Android Academy
246. Lambdas { println( "Hello Android Academy" ) }() => Hello Android Academy
247. Lambdas val sayHello = {println("Hello Android Academy")} sayHello()
248. Lambdas val sayHello = { println("Hello Android Academy")} sayHello()
249. Lambdas val sayHello = { println("Hello Android Academy")} sayHello()
250. Lambdas val sayHello = { println("Hello Android Academy")} sayHello() => Hello Android Academy
251. Lambdas - with arguments { students: Int -> students * 2 }
252. Lambdas - with arguments { students: Int -> students * 2 }
253. Lambdas - with arguments { students: Int -> students * 2 } Function arrow
254. Lambdas - with arguments { students: Int -> students * 2 } parameters
255. Lambdas - with arguments { students: Int -> students * 2 } body
256. Lambdas - with arguments { students: Int -> students * 2 }
257. Lambdas val growth = { students: Int -> students * 2 }
258. Lambdas - function types val growth: (Int) -> Int = { students: Int -> students * 2 }
259. Lambdas - function types val growth: (Int) -> Int = { students: Int -> students * 2 }
260. Lambdas - function types val growth: (Int) -> Int = { students: Int -> students * 2 }
261. Lambdas - function types val growth: (Int) -> Int = { students -> students * 2 }
262. Lambdas - example val currentStudents = 100 val growth: (Int) -> Int = { students -> students * 2 } println("new students counts is " + growth(currentStudents) )
263. Lambdas - example val currentStudents = 100 val growth: (Int) -> Int = { students -> students * 2 } println("new students counts is " + growth(currentStudents) )
264. Lambdas - example val currentStudents = 100 val growth: (Int) -> Int = { students -> students * 2 } println("new students counts is " + growth(currentStudents) )
265. Lambdas - example val currentStudents = 100 val growth: (Int) -> Int = { students -> students * 2 } println("new students counts is " + growth(currentStudents) )
266. Lambdas - example val currentStudents = 100 val growth: (Int) -> Int = { students -> students * 2 } println("new students counts is " + growth(currentStudents) )
267. Lambdas - example val currentStudents = 100 val growth: (Int) -> Int = { students -> students * 2 } println("new students counts is " + growth(currentStudents) ) //new students counts is 200
268. Lambdas - example val currentStudents = 100 val growth: (Int) -> Int = { students -> students * 2 } println("new students counts is " + growth(currentStudents) ) //new students counts is 200
269. WORKSHOP!!!
270. Classes
271. Classes class IceCream(flavor: String, cone: Boolean) { var flavor: String = flavor val cone: Boolean = cone }
272. Classes class IceCream(flavor: String, cone: Boolean) { var flavor: String = flavor val cone: Boolean = cone }
273. Classes class IceCream(flavor: String, cone: Boolean) { var flavor: String = flavor val cone: Boolean = cone }
274. Classes class IceCream(flavor: String, cone: Boolean) { var flavor: String = flavor val cone: Boolean = cone }
275. Classes class IceCream(flavor: String, cone: Boolean) { var flavor: String = flavor val cone: Boolean = cone }
276. Classes class IceCream(flavor: String, cone: Boolean) { var flavor: String = flavor val cone: Boolean = cone }
277. Classes class IceCream(var flavor: String, val cone: Boolean)
278. Classes class IceCream(var flavor: String, val cone: Boolean)
279. Classes class IceCream(var flavor: String, val cone: Boolean)
280. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean)
281. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true)
282. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true)
283. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true) val vanillaCone = IceCream()
284. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true) val vanillaCone = IceCream() val chocolateCone = IceCream("Chocolate")
285. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true) val vanillaCone = IceCream() val chocolateCone = IceCream("Chocolate") val vanillaCup = IceCream(cone = false)
286. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true) val vanillaCone = IceCream() val chocolateCone = IceCream("Chocolate") val vanillaCup = IceCream(cone = false)
287. Classes - Declaring Properties
288. Classes - Declaring Properties class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val cup = !cone }
289. Classes - Declaring Properties class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val cup = !cone val base = if(cup) "cup" else "cone" }
290. Classes - Declaring Properties class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val cup = !cone val base = if(cup) "cup" else "cone" var flavorString = "I taste like $flavor" }
291. Classes - Declaring Properties class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val cup = !cone val base = if(cup) "cup" else "cone" var flavorString: String? }
292. Classes - Declaring Properties class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val cup = !cone val base = if(cup) "cup" else "cone" var flavorString: String? } // ERROR: Property must be initialized or be abstract.
293. Classes - Declaring Properties class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val cup = !cone val base = if(cup) "cup" else "cone" var flavorString: String? } // ERROR: Property must be initialized or be abstract.
294. Classes - Declaring Properties class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val cup = !cone val base = if(cup) "cup" else "cone" val flavorString: String? } // ERROR: Property must be initialized or be abstract.
295. Classes - Declaring Properties class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val cup = !cone val base = if(cup) "cup" else "cone" val flavorString: String? init { flavorString = "I taste like $flavor" } }
296. Classes - Declaring Properties class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val cup = !cone val base = if(cup) "cup" else "cone" val flavorString: String? init { flavorString = "I taste like $flavor" } }
297. Classes - Declaring Properties val <propertyName>[: <PropertyType>] [= <property_initializer>] [<getter>] [<setter>]
298. Classes - Declaring Properties val <propertyName>[: <PropertyType>] [= <property_initializer>] [<getter>] [<setter>]
299. Classes - Declaring Properties var <propertyName>[: <PropertyType>] [= <property_initializer>] [<getter>] [<setter>]
300. Classes - Declaring Properties var <propertyName>[: <PropertyType>] [= <property_initializer>] [<getter>] [<setter>] var flavorString = "I taste like $flavor"
301. Classes - Declaring Properties var <propertyName>[: <PropertyType>] [= <property_initializer>] [<getter>] [<setter>] var flavorString = "I taste like $flavor"
302. Classes - Declaring Properties var <propertyName>[: <PropertyType>] [= <property_initializer>] [<getter>] [<setter>] var flavorString = "I taste like $flavor"
303. Classes - Declaring Properties var <propertyName>[: <PropertyType>] [= <property_initializer>] [<getter>] [<setter>] val flavorString: String? init{ flavorString = "I taste like $flavor" }
304. Classes - Declaring Properties var <propertyName>[: <PropertyType>] [= <property_initializer>] [<getter>] [<setter>] var flavorString = "I taste like $flavor"
305. Classes - Declaring Properties var <propertyName>[: <PropertyType>] [= <property_initializer>] [<getter>] [<setter>] var flavorString = "I taste like $flavor"
306. Classes - Getters and Setters
307. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" }
308. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" }
309. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" }
310. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" }
311. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla get() = this.flavor == "Vanilla" }
312. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla = false get() = this.flavor == "Vanilla" } // ERROR - Initializer is not allowed here because // this property has no backing field
313. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla get() = this.flavor == "Vanilla" }
314. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" } val iceCream = IceCream()
315. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" } val iceCream = IceCream()
316. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" } val iceCream = IceCream() println(iceCream.isVanilla)
317. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" } val iceCream = IceCream() println(iceCream.isVanilla)
318. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" } val iceCream = IceCream() println(iceCream.isVanilla)
319. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" } val iceCream = IceCream() println(iceCream.isVanilla)
320. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" } val iceCream = IceCream() println(iceCream.isVanilla) // true
321. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" } val iceCream = IceCream() println(iceCream.isVanilla) // true iceCream.flavor = "Chocolate"
322. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" } val iceCream = IceCream() println(iceCream.isVanilla) // true iceCream.flavor = "Chocolate" println(iceCream.isVanilla)
323. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" } val iceCream = IceCream() println(iceCream.isVanilla) // true iceCream.flavor = "Chocolate" println(iceCream.isVanilla)
324. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla: Boolean get() = this.flavor == "Vanilla" } val iceCream = IceCream() println(iceCream.isVanilla) // true iceCream.flavor = "Chocolate" println(iceCream.isVanilla) // false
325. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla get() = this.flavor == "Vanilla" }
326. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ val isVanilla get() = this.flavor == "Vanilla" }
327. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" }
328. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" } // ERROR: Property must be initialized.
329. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } }
330. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } }
331. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } }
332. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } }
333. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate")
334. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}")
335. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") Chocolate , false
336. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") Chocolate , false
337. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") Chocolate , false
338. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") iceCream.isVanilla = true
339. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") iceCream.isVanilla = true
340. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") iceCream.isVanilla = true
341. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") iceCream.isVanilla = true println("${iceCream.flavor} , ${iceCream.isVanilla}")
342. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") iceCream.isVanilla = true println("${iceCream.flavor} , ${iceCream.isVanilla}")
343. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") iceCream.isVanilla = true println("${iceCream.flavor} , ${iceCream.isVanilla}") Vanilla , true
344. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") iceCream.isVanilla = true println("${iceCream.flavor} , ${iceCream.isVanilla}") Vanilla , true
345. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") iceCream.isVanilla = true println("${iceCream.flavor} , ${iceCream.isVanilla}") Vanilla , true
346. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Chocolate") println("${iceCream.flavor} , ${iceCream.isVanilla}") iceCream.isVanilla = true println("${iceCream.flavor} , ${iceCream.isVanilla}") Vanilla , true
347. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } }
348. Classes - Getters and Setters class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true)
349. Classes
350. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ constructor(topping: String): this() { cone = false } }
351. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ constructor(topping: String): this() { cone = false } }
352. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ constructor(topping: String): this() { cone = false } }
353. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ constructor(topping: String): this() { cone = false } }
354. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ constructor(topping: String): this("Chocolate", false) { cone = false } }
355. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ constructor(topping: String): this() { cone = false } }
356. Classes class IceCream(var flavor: String = "Vanilla", val cone: Boolean = true){ constructor(topping: String): this() { cone = false } }
357. Classes Secondary Constructors: • Calls the primary constructor (this()) • Cannot assign val/ var to secondary constructor arguments • Get called last
358. Classes Secondary Constructors: • Calls the primary constructor (this()) • Cannot assign val/ var to secondary constructor arguments • Get called last
359. Classes Secondary Constructors: • Calls the primary constructor(this()) • Cannot assign val/ var to secondary constructor arguments • Get called last
360. Classes Secondary Constructors: • Calls the primary constructor(this()) • Cannot assign val/ var to secondary constructor arguments • Get called last
361. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ constructor(topping: String): this() { cone = false } }
362. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone constructor(topping: String): this() { cone = false } }
363. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone constructor(topping: String): this() { cone = false } var base = if(cup) "cup" else "cone" }
364. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone init {/*do something with ice-cream*/} constructor(topping: String): this() { cone = false } var base = if(cup) "cup" else "cone" }
365. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone init {/*do something with ice-cream*/} constructor(topping: String): this() { cone = false } init {/*do something with ice-cream*/} var base = if(cup) "cup" else "cone" init {/*do something with ice-cream*/} }
366. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone init {/*do something with ice-cream*/} constructor(topping: String): this() { cone = false } init {/*do something with ice-cream*/} var base = if(cup) "cup" else "cone" init {/*do something with ice-cream*/} }
367. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone init {/*do something with ice-cream*/} constructor(topping: String): this() { cone = false } init {/*do something with ice-cream*/} var base = if(cup) "cup" else "cone" init {/*do something with ice-cream*/} }
368. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone init {/*do something with ice-cream*/} constructor(topping: String): this() { cone = false } init {/*do something with ice-cream*/} var base = if(cup) "cup" else "cone" init {/*do something with ice-cream*/} }
369. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone init {/*do something with ice-cream*/} constructor(topping: String): this() { cone = false } init {/*do something with ice-cream*/} var base = if(cup) "cup" else "cone" init {/*do something with ice-cream*/} }
370. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone init {/*do something with ice-cream*/} constructor(topping: String): this() { cone = false } init {/*do something with ice-cream*/} var base = if(cup) "cup" else "cone" init {/*do something with ice-cream*/} }
371. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone init {/*do something with ice-cream*/} constructor(topping: String): this() { cone = false } init {/*do something with ice-cream*/} var base = if(cup) "cup" else "cone" init {/*do something with ice-cream*/} }
372. Classes class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone init {/*do something with ice-cream*/} constructor(topping: String): this() { cone = false } init {/*do something with ice-cream*/} var base = if(cup) "cup" else "cone" init {/*do something with ice-cream*/} }
373. Visibility Modifiers
374. Visibility Modifiers • public • private • internal • protected
375. Visibility Modifiers • public - declarations are visible everywhere • private - visible inside the file/class containing the declaration • internal - visible inside the same module • protected - visible inside the class and its subclasses
376. Visibility Modifiers • public - declarations are visible everywhere • private - visible inside the file/class containing the declaration • internal - visible inside the same module • protected - visible inside the class and its subclasses
377. Visibility Modifiers • public - declarations are visible everywhere • private - visible inside the file/class containing the declaration • internal - visible inside the same module • protected - visible inside the class and its subclasses
378. Visibility Modifiers • public - declarations are visible everywhere • private - visible inside the file/class containing the declaration • internal - visible inside the same module • protected - visible inside the class and its subclasses
379. Visibility Modifiers class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone init {/*do something with ice-cream*/} constructor(topping: String): this(){ cone = false } init {/*do something with ice-cream*/} var base = if(cup) "cup" else "cone" init {/*do something with ice-cream*/} }
380. Visibility Modifiers class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone constructor(topping: String): this(){ cone = false } var base = if(cup) "cup" else "cone" }
381. Visibility Modifiers class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone constructor(topping: String): this(){ cone = false } var base = if(cup) "cup" else "cone" }
382. Visibility Modifiers class IceCream(var flavor: String = "Vanilla", var cone: Boolean = true){ val cup = !cone constructor(topping: String): this(){ cone = false } var base = if(cup) "cup" else "cone" var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } }
383. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } }
384. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } }
385. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } }
386. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } }
387. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles")
388. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles")
389. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles")
390. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor
391. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor
392. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible
393. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone
394. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone
395. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible
396. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup
397. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup
398. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible
399. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base
400. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base
401. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible
402. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla
403. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla
404. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla
405. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla
406. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" protected var isVanilla get() = this.flavor == "Vanilla" set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla
407. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" var isVanilla protected get() = this.flavor == "Vanilla" protected set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla
408. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" var isVanilla protected get() = this.flavor == "Vanilla" protected set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla //not visible
409. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" var isVanilla protected get() = this.flavor == "Vanilla" protected set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla //not visible
410. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" var isVanilla public get() = this.flavor == "Vanilla" protected set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla //not visible
411. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" var isVanilla public get() = this.flavor == "Vanilla" protected set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla//visible
412. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" var isVanilla public get() = this.flavor == "Vanilla" protected set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla//visible iceCream.isVanilla = false
413. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" var isVanilla public get() = this.flavor == "Vanilla" protected set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla//visible iceCream.isVanilla = false
414. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" var isVanilla public get() = this.flavor == "Vanilla" protected set(value) { if(value) flavor = "Vanilla" } } val iceCream = IceCream("Sprinkles") iceCream.flavor //visible iceCream.cone //visible iceCream.cup //visible iceCream.base //not visible iceCream.isVanilla//visible iceCream.isVanilla = false //not
415. Visibility Modifiers internal class IceCream private constructor( public var flavor: String = "Vanilla", internal var cone: Boolean = true) { public val cup = !cone internal constructor(topping: String): this(){ cone = false } protected var base = if(cup) "cup" else "cone" var isVanilla public get() = this.flavor == "Vanilla" protected set(value) { if(value) flavor = "Vanilla" } }
416. Visibility Modifiers • Local declarations
417. Visibility Modifiers • Local declarations - Local variables, functions and classes can not have visibility modifiers.
418. WORKSHOP!!!