How to format a numerical value?

[valterc]

Hi,

I have a datatype that emits a single double value, for example:

    <DataType
        description="Example datatype."
        displayName="Example datatype"
        typeId="DATATYPE_EXAMPLE" />

class ExampleDataType(extension: String) : DataTypeImpl(extension, "DATATYPE_EXAMPLE") {

  override fun startStream(emitter: Emitter<StreamState>) {
    val job = CoroutineScope(Dispatchers.IO).launch {
                while (true) {
                    emitter.onNext(
                            StreamState.Streaming(
                                DataPoint(
                                    dataTypeId,
                                    values = mapOf(DataType.Field.SINGLE to random() * 10),
                                )
                            )
                        )
                    delay(5_000)
                }
            }
    
    emitter.setCancellable {
                job.cancel()
    }
  }

}

If I add this datatype to a profile, only the integer part of the value is displayed (example: 5), no decimal places are presented (example: 5.37). Is there a way to 'format' the value or do we need to use a graphical datatype with a custom view?

I also saw that we can emit an UpdateGraphicConfig with a formatDataTypeId, but it's a bit unclear what do we need to provide in this parameter, tried with SPEED and DISTANCE, but no luck.

    override fun startView(context: Context, config: ViewConfig, emitter: ViewEmitter) {
        emitter.onNext(UpdateGraphicConfig(formatDataTypeId = DataType.Type.SPEED))
    }

Thanks.

[brentnd]

Try with UpdateNumericConfig with DataType.Type.INTENSITY_FACTOR as an experiment. This field uses 2 digits of precision with no value conversion (speed and distance will try to go from meters to the appropriate miles/km based on user profile).

[valterc]

That one works, showing the two decimal places. Thank you!

(It would be great if there was some docs/examples explaining the different behaviors when using the different types. In the future, maybe even allowing for custom format strings format="#.00", format="00.0", ...)

[refi-git]

Thanks for reporting, I thought only me had this issue. :D
The workaround works, thanks @brentnd