How to use set query function in webform usage in frappe

frappe.ui.form.on(‘Participant_Grp_Mst’, {
refresh: function(frm) {
cur_frm.set_query(“event_id”, function() {
return {
filters: {
is_active: “1”

How to customize the above function to use it in a frappe web form where the event status is active and only needs to fetch…
As above logic, i have used to for doctype, and its working fine but i need to use it in frappe web form…