You won't be able to do it without getting into a Data Expression. The Advanced Formatting profile in Arcade can't see beyond the individual datapoint, so there's no way to grab attributes from another place.
var fs = FeatureSetByPortalItem(
Portal('your portal url'),
'itemid of service',
0, // or other layer index
['ID_num', 'Title', 'Related_nums', 'Pdf_link'],
false
)
// get the links as own dict in ID:Link format
var link_dict = {}
for (var f in fs) {
link_dict[f['ID_num']] = f['Pdf_link']
}
// output dict taking incoming schema plus a new field for links
var out_dict = {
fields: Splice(Schema(fs)['fields'], {name:'rel_links', type: 'esriFieldTypeString'}),
geometryType: '',
features: []
)
// loop through featureset
for (var f in fs) {
// get array of related numbers
var rel_num = Split(f['Related_nums'], ', ')
// loop through and build related link dict
var rel_link_dict = []
for (var n in rel_num) {
rel_link_dict[`link ${rel_num[n]}`] = link_dict[rel_num[n]]
}
// push attributes into out dict
Push(
out_dict['features'],
{ attributes: {
ID_num: f['ID_num'],
Title: f['Title'],
Related_nums: f['Related_nums'],
Pdf_link: f['Pdf_link'],
rel_links: Text(rel_link_dict)
}}
)
}
return FeatureSet(Text(out_dict))
There is admittedly a lot going on here, and I don't have similar data handy for testing, but I'll explain some key points.
While we could just spit out the links as a single text field, you'll run into a problem when you try to turn those into links. No matter what, you will need to use Advanced Formatting to turn the rel_links field into legitimate HTML in your list item.
Even if we had a list of "link 1, link 2" and used split to break it apart, how would we know which link was which anymore?
By loading the entire dict into a text field, you'll end up with a big string, something like:
{"link 1": "link from feature 1", "link 4": "link from feature 4"} And we can pass that into FromJSON in the Advanced Formatting section to work with it as a dict again. It's a great way of passing variable-length lists of features / attributes from a Data Expression into the Advanced Formatting section. In your advanced formatting expression, you could try something like this:
var rel_links = FromJSON($datapoint['rel_links'])
var link_arr = []
for (var l in rel_links) {
Push(
link_arr,
`<a href="${rel_link[l]}">${l}</a>`
)
}
var link_text = Concatenate(link_arr, '<br>')
return {
attributes: {
link_text
}
}
Maybe that's more complicated than you were hoping for. 😬
But I do think it could work!
- Josh Carlson
Kendall County GIS
