Mobile Programming enum

モバイルプログラミングの授業で使うスライドです

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1. ྻڍܕ MOBILE PROGRAMMING 12TH DEC
2. 1. ྻڍܕʁ
3. ςΩετ ྻڍܕ(ENUM)ͱ͸ʁ ▸ ؔ࿈͢Δ஋ΛҰͭͷܕͱͯ͠·ͱΊͨ΋ͷ ▸ ྫ͑͹ϙέϞϯͷλΠϓͳͲ͸ྻڍܕ(enum)Ͱද͢͜ͱ͕Ͱ ͖Δ ▸ λΠϓͰॲཧΛ෼͚͍ͨ৔߹จࣈྻ΍਺ࣈΛ࢖͏ΑΓ΋enum Λ࢖͏ํ͕ϛεΛແ͘͠΍͘͢ɺ҆શʹ࣮૷͢Δ͜ͱ͕Ͱ͖Δ ▸ จ๏͸enum <EnumName> { case member1 case member2 }
4. ςΩετ ࣮ࡍͷίʔυ(ENUMͷఆٛ) // ϙέϞϯͷλΠϓΛEnumͰ·ͱΊͨ৔߹ enum PokemonType { case fire // ΄ͷ͓λΠϓ case grass // ͘͞λΠϓ case water // ΈͣλΠϓ case normal // ϊʔϚϧλΠϓ }
5. ςΩετ ࣮ࡍͷίʔυ(ม਺ʹೖΕΔ) // ϙέϞϯͷλΠϓΛEnumͰ·ͱΊͨ৔߹ enum PokemonType { case fire // ΄ͷ͓λΠϓ case grass // ͘͞λΠϓ case water // ΈͣλΠϓ case normal // ϊʔϚϧλΠϓ } var pokemonType: PokemonType pokemonType = PokemonType.fire // جຊܕ pokemonType = .grass // ܕͷ໊લ͸লུՄೳ
6. ςΩετ ࣮ࡍͷίʔυ(ϓϩύςΟ΍ϝιου΋ఆٛͰ͖·͢) enum PokemonType { // লུ… func getTypeString() -> String { switch self { case .fire: return "΄ͷ͓" case .grass: return "͘͞" case .water: return "Έͣ" case .normal: return "ϊʔϚϧ" } } } var pokemonType: PokemonType = .fire print(pokemonType.getTypeString()) // ϝιουݺͼग़͠
7. 2. ENUMʹ͍ͭͯ
8. ςΩετ ENUMͷಛ௃ ▸ switch(NintendoͰͳ͍)Ͱ enum Λ࢖͏৔߹defaultΛॻ͔ ͳͯ͘͢Ή(໢ཏνΣοΫ) ▸ ϝϯόʔ͕஋Λ࣋ͨͤΔ͜ͱ͕Ͱ͖Δ (஋ܕenum) ▸ ϝϯόʔʹؔ࿈͢ΔܕΛ͚ͬͭ͘Δ͜ͱ͕Ͱ͖Δ (ؔ࿈ܕ enum)
9. 2-1. ENUMͷ໢ཏ νΣοΫ
10. ςΩετ ໢ཏνΣοΫ? ▸ enum Ͱ switchͰ৚݅෼ذΛߦ͏ࡍʹνΣοΫ͕ೖΔ ▸ ͦͷenumͷϝϯό͕શͯྻڍ͞Ε͍ͯΔ͔ΛνΣοΫͯ͠ ଍Γͳ͍৔߹͸ΤϥʔΛग़͢(ίϯύΠϧΤϥʔ) ▸ ྻڍܕͷϝϯό͸਺͕ܾ·͍ͬͯΔͷͰ͜ͷΑ͏ͳνΣοΫ ͕Մೳ ▸ ΤϥʔΛղফ͢Δʹ͸શͯͷϝϯόΛྻڍ͢Δ͔ default Λ هड़͢Δ
11. ςΩετ ࣮ࡍͷίʔυ(͜ͷΑ͏ͳENUM͕͋ͬͨ৔߹) // ϙέϞϯͷλΠϓΛEnumͰ·ͱΊͨ৔߹ enum PokemonType { case fire // ΄ͷ͓λΠϓ case grass // ͘͞λΠϓ case water // ΈͣλΠϓ case normal // ϊʔϚϧλΠϓ }
12. ςΩετ ࣮ࡍͷίʔυ(͜Μͳ෩ʹνΣοΫ͕͞Ε·͢) // ͬͪ͜͸OK(ϝϯό͕શͯྻڍ͞Ε͍ͯΔ) func getTypeString() -> String { switch self { case .fire: return "΄ͷ͓" case .grass: return "͘͞" case .water: return "Έͣ" case .normal: return "ϊʔϚϧ" } } // ͬͪ͜͸NG(ϝϯό͕શͯྻڍ͞Ε͍ͯͳ͍) func getTypeString() -> String { switch self { case .fire: return "΄ͷ͓" case .grass: return "͘͞" case .water: return "Έͣ" } } // ͬͪ͜΋OK(ϝϯό͕શͯྻڍ͞Ε͍͍ͯͳ͍͕default͕͋Δ) func getTypeString() -> String { switch self { case .fire: return "΄ͷ͓" case .grass: return "͘͞" default: return “ϊʔϚϧ" } } // ͬͪ͜΋NG(default͕༨ܭ) func getTypeString() -> String { switch self { case .fire: return "΄ͷ͓" case .grass: return "͘͞" case .water: return "Έͣ" case .normal: return “ϊʔϚϧ" default: return "ϊʔϚϧ" } }
13. 2-2. ஋ܕENUM
14. ςΩετ ஋ܕENUM? ▸ enumͷϝϯόʹInt, Float(or Double), String ͷ஋Ληοτͨ͠ Enumͷ͜ͱ ▸ จ๏͸ enum <EnumName>: Type { case member1 = <value> … } ▸ ϝϯόʹ༩͑ΒΕͨ஋͸ variable.rawValue ͱ͍͏ܗͰऔಘ͕Մೳ ▸ ·ͨ EnumName(rawValue: <value>) ͱ͍͏ܗͰenumͷऔಘ͕ Մೳ
15. ςΩετ ࣮ࡍͷίʔυ(STRINGΛ࢖ͬͨ৔߹) // ϙέϞϯͷλΠϓʹจࣈΛ௥Ճ enum PokemonType: String { case fire = "΄ͷ͓" case grass = "͘͞" case water = "Έͣ" case normal = "ϊʔϚϧ" } var pokemonType = PokemonType(rawValue: "΄ͷ͓") ?? .normal // enumΛ࡞੒ print(pokemonType.rawValue)
16. 2-3. ؔ࿈ܕENUM
17. ςΩετ ؔ࿈ܕENUM? ▸ Enumͷϝϯόʹରͯؔ͠࿈͢ΔܕΛࢦఆ͢Δ͜ͱͷͰ͖Δ ػೳ ▸ ஋ܕͷEnumͱ͸ҧ͍ϝϯόʹܕ͚ͩΛࢦఆ͢Δ ▸ จ๏͸ enum <EnumName>: Type { case member1(Type) … } ▸ ͲΜͳঢ়ଶ͔ͱ͍͏͜ͱ͚ͩͰͳͦ͘Εʹ෇ਵ͢Δ෇Ճ৘ใ Λ͚ͬͭ͘Δ͜ͱ͕Ͱ͖Δ
18. ۩ମྫ
19. ςΩετ ͜ΕΛ࣮૷͍ͨ͠
20. ςΩετ ۩ମྫ func formattedPostDateTime(datetime: Int) -> String { // ࣮૷... } // Ҿ਺ʹͲΕ͘Β͍લ͔࣌ؒΛ༩͑ͯϑΥʔϚοτ formattedPostDateTime(datetime: 10)
21. Μʁ
22. ςΩετ ۩ମྫ func formattedPostDateTime(datetime: Int) -> String { // ࣮૷... } // Ҿ਺ʹͲΕ͘Β͍લ͔࣌ؒΛ༩͑ͯϑΥʔϚοτ formattedPostDateTime(datetime: 10) // <- "10" ͸ 10೔લʁ 10࣌ؒ લʁ 10෼લʁ 10ඵલʁ
23. ୯ҐΛ༩͑ΔͷΛ ๨Ε͍ͯ·ͨ͠
24. ςΩετ ͜ΕͰOK…? // Ҿ਺ʹ࣌ؒͷ୯ҐΛ௥Ճ func formattedPostDateTime(datetime: Int, termType: Int) -> String { switch termType { case 0: return "\(datetime)೔લ" case 1: return "\(datetime)࣌ؒલ" // লུ... default: return "গ͠લ" } }
 // Ҿ਺ʹͲΕ͘Β͍લ͔࣌ؒΛ༩͑ͯϑΥʔϚοτ formattedPostDateTime(datetime: 10, termType: 0)
25. Μʁ
26. ςΩετ ͜ΕͰOK…? // Ҿ਺ʹ࣌ؒͷ୯ҐΛ௥Ճ func formattedPostDateTime(datetime: Int, termType: Int) -> String { switch termType { case 0: return "\(datetime)೔લ" case 1: return "\(datetime)࣌ؒલ" // লུ... default: return "গ͠લ" } }
 // Ҿ਺ʹͲΕ͘Β͍લ͔࣌ؒΛ༩͑ͯϑΥʔϚοτ formattedPostDateTime(datetime: 10, termType: 0) // <- 0 ͩͱ n೔લʹͳΔΜ͚ͩͬʁ n࣌ؒલʹͳΔʁ
27. ੔਺Ͱ͸Θ͔Γ ʹ͍͘
28. ͦΕENUMͰ΍ Γ·ͤΜ͔ʁ
29. ςΩετ ͜ΕͰ΋͍͍͚Ͳ…? // ࣌ؒͷ୯ҐΛද͢EnumΛ௥Ճ enum DateTerm { case day case hours case minutes case seconds } // Ҿ਺ʹ౉࣌ؒ͢ͷ୯ҐΛInt͔ΒDateTermʹมߋ func formattedPostDateTime(datetime: Int, termType: DateTerm) -> String { switch termType { case .day: return "\(datetime)೔લ" case .hours: return "\(datetime)࣌ؒલ" // লུ... } } // Ҿ਺ʹͲΕ͘Β͍લ͔IntͱDateTermΛ༩͑ͯϑΥʔϚοτ formattedPostDateTime(datetime: 10, termType: .day)
30. Ͱ͖Ε͹Ҿ਺͸গͳ ͍ํ͕خ͍͚͠ Ͳɾɾɾ
31. ͦΕEnumͰ(ry
32. ςΩετ ؔ࿈ܕENUMΛ࢖͑͹ɾɾɾ // DateTermͷϝϯόʹؔ࿈͢Δܕ(ࠓճ͸Int)Λ௥Ճ enum DateTerm { case day(Int) case hours(Int) case minutes(Int) case seconds(Int) } // Ҿ਺ΛDateTermҰͭʹ·ͱΊΒΕͨʂ func formattedPostDateTime(from term: DateTerm) -> String { switch term { case .day(let value): return “\(value)೔લ" // <- value ʹ͸10͕ೖ͍ͬͯΔ case .hours(let value): return "\(value)࣌ؒલ" // লུ… } } // 10೔લͱϑΥʔϚοτ formattedPostDateTime(from: .day(10))
33. ςΩετ BEFORE // Ҿ਺ʹ࣌ؒͷ୯ҐΛ௥Ճ func formattedPostDateTime(datetime: Int, termType: Int) -> String { switch termType { case 0: return "\(datetime)೔લ" case 1: return "\(datetime)࣌ؒલ" // লུ... default: return "গ͠લ" } }
 // Ҿ਺ʹͲΕ͘Β͍લ͔࣌ؒΛ༩͑ͯϑΥʔϚοτ formattedPostDateTime(datetime: 10, termType: 0)
34. ςΩετ AFTER enum DateTerm { case day(Int) case hours(Int) case minutes(Int) case seconds(Int) } func formattedPostDateTime(from term: DateTerm) -> String { switch term { case .day(let value): return “\(value)೔લ" case .hours(let value): return "\(value)࣌ؒલ" // লུ… } } formattedPostDateTime(from: .day(10))