Using the Arcade Split function to create a list element in ArcGIS Dashboard

Question

I am making a dashboard in ArcGIS Online. (see figure)

I want to create a list for users to select their biomass of interest and use them as a filter for the diagrams on the right. The current names in the list are ugly (for lack of a better word). I want to remove everything contained in brackets. For this purpose, I used Arcade's Split() function as follows:

Split(Text($datapoint["Nom_biomasse"])," (",1)[0]

However, the result is still the exact same as $datapoint["Nom_biomasse"] (the field containing the biomass names) on its own.

Is there something I am doing wrong or is this just something that cannot be done with dashboard lists?

It seems the Split() function inside the expression works fine. However, I am unable to reference it in the list itself.

Answer 1

I figured it out eventually. May this serve as an illustration to the ArcGIS online help.

When enabling advanced formatting, there is a sample code available. My mistake was to ignore this sample code and write my expression from scratch. Following the sample structure, here is my current Arcade expression:

return {
  textColor: '',
  backgroundColor: '',
  separatorColor:'',
  selectionColor: '',
  selectionTextColor: '',
  attributes: {
        attribute2: Split($datapoint["Nom_biomasse"], " (")[0]
  }
}

The attribute2 can then be referenced in the list with the following expression:

{expression/attribute2}

(see figure)