SwiftのEnum Associated Valuesを Kotlinでエミュレートしたい

Transcript

1. Ո଒ͷຖ೔Λ΋ͬͱসإʹɻ
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2. ෋ా݈ೋ
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3. ΞδΣϯμ
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4. Ո଒ͷຖ೔Λ΋ͬͱসإʹɻ
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5. ͦ΋ͦ΋Կʁ
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6. 4XJGUͷ&OVNܕʹͯ೚ҙͷܕΛ֨ೲ͢
   Δ͜ͱ͕Ͱ͖·͢
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7. enum ListItemType {
   case header(Int, String)
   case row1(Int, String, Int)
   case row2(Int, String)
   case row3(Int, String)
   case footer(Int, String)
   }
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8. ศརʂʂ
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9. ,PUMJO͸ʜ
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10. enum class ListItemType(val id: Int, val title: String) {

    HEADER(1, "header"),

    ROW1(2, "row1"),

    ROW2(3, "row2"),

    ROW3(4, "row3"),

    FOOTER(5, "footer"),

    }
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11. enum class ListItemType(val id: Int, val title: String) {

    HEADER(1, "header"),

    ROW1(2, "row1", “image_url"), // ίϯύΠϧΤϥʔ

    ROW2(3, "row2"),

    ROW3(4, "row3"),

    FOOTER(5, "footer"),

    }
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12. ,PUMJOʹ͸&OVN"TTPDJBUFE7BMVFT
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14. ϦετͷϏϡʔλΠϓ΍ΠϕϯτλΠϓΛ
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15. Ո଒ͷຖ೔Λ΋ͬͱসإʹɻ
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16. "OESPJE։ൃʹ͓͍ͯɺ3FDZDMFS7JFXͷ
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17. ϕʔεͱͳΔجఈΫϥεΛ࡞ΓɺͦΕ
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18. ΞϓϩʔνʢجఈΫϥεʣ
    open class BaseListItem(

    open val id: Int,

    open val title: String

    )

    

    data class ListItem1(

    override val id: Int,

    override val title: String,

    val mainImageUrl: Int

    ) : BaseListItem(id, title)

    

    data class ListItem2(

    override val id: Int,

    override val title: String,

    val mainImageUrl: String,

    val subImageUrl: String

    ) : BaseListItem(id, title)
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19. ΞϓϩʔνʢλΠϓ෼͚ʣ
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20. ΞϓϩʔνʢλΠϓ෼͚ʣ
    enum class ListItemType {

    HEADER, ROW1, ROW2, ROW3, FOOTER

    }

    

    data class ListItem(val id: String = "",

    val title: String = "",

    val type: ListItemType = ListItemType.HEADER)

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21. 4XJGUΈ͍ͨʹ&OVNͰ؅ཧͯ͠Έ͍ͨ
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22. ,PUMJOͰ΋ͬͱ؆୯ʹͰ͖ͳ͍͔ͳʜ
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23. 4FBMFE$MBTT
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24. 4FBMFE$MBTT͸ܧঝΛ੍ݶͰ͖ɺωετ͠
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26. sealed class ListItemType {

    class Header(val id: Int, val title: String) : ListItemType()

    class Footer(val id: Int, val title: String) : ListItemType()

    }
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27. 3FMBYFE3VMFTGPS4FBMFE$MBTTFT
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28. ,PUMJO͔Β4FBMFE$MBTTͰ%BUB
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29. sealed class ListItemType {

    data class Header(val id: Int, val title: String) : ListItemType()

    data class Row1(val id: Int, val title: String, val imageUrl: String) : ListItemType()

    data class Row2(val id: Int, val title: String) : ListItemType()

    data class Row3(val id: Int, val title: String) : ListItemType()

    data class Footer(val id: Int, val title: String) : ListItemType()

    }
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30. %BUB$MBTTʹ͸ɺFRVBMTɺIBTI$PEFɺ
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31. %BUB$MBTT͸σʔλͷ੔߹ੑΛकΔͨ
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32. sealed class ListItemType {

    data class Header(val id: Int, val title: String) : ListItemType()

    data class Row1(val id: Int, val title: String, val imageUrl: String) : ListItemType()

    data class Row2(val id: Int, val title: String) : ListItemType()

    data class Row3(val id: Int, val title: String) : ListItemType()

    data class Footer() : ListItemType() // ίϯύΠϧΤϥʔ

    }
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33. Ҿ਺ͷͳ͍΋ͷʹ͍ͭͯ͸ɺ$MBTTͰ
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34. sealed class ListItemType {

    data class Header(val id: Int, val title: String) : ListItemType()

    data class Row1(val id: Int, val title: String, val imageUrl: String) : ListItemType()

    data class Row2(val id: Int, val title: String) : ListItemType()

    data class Row3(val id: Int, val title: String) : ListItemType()

    class Footer() : ListItemType()

    }
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35. ϦετͷϏϡʔλΠϓ΍ΠϕϯτλΠ
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36. Ո଒ͷຖ೔Λ΋ͬͱসإʹɻ
    ·ͱΊ
    

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37. 4XJGU&OVN"TTPDJBUFE7BMVFTͷ୅ସҊͱ͠
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38. Ո଒ͷຖ೔Λ΋ͬͱসإʹɻ
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