How to set a fixed value for a item in Retrofit

Question

I have a data class which is populated by retrofit. The server (API) has no id field in it. So I created a val id and assigned it some value say 69. But once I receive the data, the value of id is not 69, but 0. Help please.

@Entity(tableName = "current_weather")
data class CurrentWeather(

    @SerializedName("last_updated_epoch")
    val lastUpdatedEpoch: Int,

// ... //

    @SerializedName("gust_kph")
    val gustKph: Float
) {
    @PrimaryKey(autoGenerate = false)
    var id: Int = 69
}

I even tried doing this:

data class CurrentWeather(

    @PrimaryKey(autoGenerate = false)
    val id: Int = 69,
// ... //
)

https://stackoverflow.com/questions/47905627/how-to-annotate-a-default-value-inside-a-android-room-entity — AskNilesh, Jul 15 '19 at 10:59
Yes I've read that, and that doesn't seem to work. And that is in java too. Can you help me for kotlin? — potatoxchip, Jul 15 '19 at 11:01
@AmitParameshwar : Probably `CurrentWeather` object contains `id` with `0`. — ρяσѕρєя K, Jul 15 '19 at 11:06
Yes it is. There is no other field named `id`. And I have tried naming it different, and it doesn't work — potatoxchip, Jul 16 '19 at 03:10
How can I use this with constructor block? Is it possible to init the values after a network call? — potatoxchip, Jul 16 '19 at 03:22
I have to store it in a db, and its table should have only 1 entry. All the fields are unique, so I had to create this id field. But its value is not what I assign. — potatoxchip, Jul 16 '19 at 03:52

tim4dev · Answer 1 · 2019-07-16T16:39:20.357

1

@Entity(tableName = "current_weather")
data class CurrentWeather(

    @PrimaryKey(autoGenerate = false)
    val id: Int = 69,

    @SerializedName("last_updated_epoch")
    val lastUpdatedEpoch: Int,

    // ... //

)

upd.

This is the object to ready to write to the database. For your case, you should write a mapper / converter from the Retrofit response object to the Data Entity data class.

edited Jul 16 '19 at 16:39

answered Jul 15 '19 at 18:09

tim4dev

2,846
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No it is not working, I am populating the data class with retrofit. and there is no `id` field in the response, I am adding that myself. Is that the cause of the problem? – potatoxchip Jul 16 '19 at 02:35

score 1 · Accepted Answer · answered Jul 16 '19 at 04:02

1

Ok, this seems to be a problem with GSON, something with serialization and deserialization as it does not support kotlin properly. Read Gson Deserialization with Kotlin, Initializer block not called for more information.

answered Jul 16 '19 at 04:02

potatoxchip

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1
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How to set a fixed value for a item in Retrofit

2 Answers2