[Python] How to reorder fields in a Flask-Admin form using an Ajax selector with scaffold_form...

I created a custom Ajax selector in a Flask-Admin view to optimize search in the birth_city_id field (over 36000 items) using form_ajax_refs (based on How to do an Ajax form field on Flask Admin implementation). While the Ajax selector works correctly, I have an issue with how fields are displayed in the form.

The birth_city_id field only appears if I add it explicitly in the scaffold_form method (I tried with form_overrides attribute too, but it's fail). However, this results in the field being placed at the end of the form, whereas it should appear before personal_information and professional_information fields.

Here’s my code:

from flask_admin.model.fields import AjaxSelectField
from flask_admin.model.ajax import AjaxModelLoader, DEFAULT_PAGE_SIZE

from ..models import *

class CityAjaxModelLoader(AjaxModelLoader):
def __init__(self, name, **options):
super(CityAjaxModelLoader, self).__init__(name, options)

def format(self, model):
if model is None:
return None
return (model.id, repr(model))

def get_one(self, pk):
return session.query(City).get(pk)

def get_list(self, query, offset=0, limit=DEFAULT_PAGE_SIZE):
search_term = query.strip().lower()
return session.query(City).filter(City.label.ilike(f"%{search_term}%")).offset(offset).limit(limit).all()

class PrinterView(GlobalModelView):

# ...

form_columns = [
"lastname",
"firstnames",
"birth_date",
"birth_city_label",
"birth_city_id",
"personal_information",
"professional_information",
]

form_ajax_refs = {
'birth_city_id': CityAjaxModelLoader('birth_city_id')
}

def scaffold_form(self):
form_class = super(PrinterView, self).scaffold_form()
form_class.birth_city_id = AjaxSelectField(
CityAjaxModelLoader('birth_city_id'),
label='Birth City (reference)',
blank_text="Select a city..."
)
# reorder fields ?
return form_class


The birth_city_id field is always placed at the end of the form, even if I explicitly include it in the form_columns list (I expected to force the fields position like this but it's change nothing).

I would like to know:

1. 
   Is there a way to reorder fields through scaffold_form method?
   
   
2. 
   Is there a better strategy to integrate an Ajax selector while maintaining the field order in the form?
   

Thanks in advance for your help!

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