How to add ListView Filter for select field type

Hello everyone,
In the employee doctype, there is a field “Sub-department”. The type is “Select”. Options are given by the client script. Now, I want to add this field to the listview filter. So I add like this.

the client sciprt for this is:
frappe.listview_settings[‘Employee’] = {
onload: function(listview) {
if(listview.page.fields_dict.sub_department){
let options = [“”];

	    let records = frappe.db.get_list('Department', {
	        filters : [['parent_department', 'not in', ['', 'All Departments']]],
	        fields : ['name']
	    }).then(res=>{
	        for(let i=0; i<res.length; i++){
	            options.push(res[i].name);
	        }
	        let sub_department_filter = listview.page.fields_dict.sub_department;
	        sub_department_filter.df.options = options;
	        sub_department_filter.refresh();
	        
	    });
	
	}
},

};

But I want it in the filter button:

Here, no options are visible.
can anyone help me with this?