How do I make the results of the polygon to be data overlay

[Fakhrynm]

I made a WebGIS for my final project. But I need help when I want to retrieve data based on the results of the polygons I created on the map. I want to retrieve existing data in the database based on polygon overlays. I need clarification about how to call Polygon if the data is in self.draw_feature.

[giswqs]

m.user_roi

[Fakhrynm]

Thank you, sir. I will ask you again later.

[Fakhrynm]

Hello sir. I have tried call back using
m.user_roi

but the result m.user_roi does not update after I draw polygon.

Here my code:

import streamlit as st
import psycopg2
import leafmap
import geopandas as gpd

Connect to the database

def app():

conn = psycopg2.connect(
database="Testing",
user="postgres",
password="admin",
host="localhost",
port="5432"
)
cursor = conn.cursor()

Retrieve data from the database

cursor = conn.cursor()
query = "SELECT latitude, longitude FROM spasial"
cursor.execute(query)
data = cursor.fetchall()

Create a Leafmap

m = leafmap.Map()

m = leafmap.Map(locate_control=True)

m.add_basemap("ROADMAP")

Get the drawn polygon from the Leafmap and convert it to a GeoDataFrame:

polygon = m.user_roi
print(polygon)
gdf_polygon = gpd.GeoDataFrame([polygon], columns=['geometry'])

# Iterate over the data and add markers

for record in data:

latitude, longitude = record[0], record[1]

m.add_marker(location=[latitude, longitude])

Convert the drawn polygon to Well-Known Text (WKT) format

wkt_polygon = gdf_polygon['geometry'].to_wkt()[0]

Perform a spatial intersection query using the drawn polygon and the database data:

intersection_query = "SELECT latitude, longitude FROM spasial WHERE ST_Intersects(ST_GeomFromText(%s), geometry)"
cursor.execute(intersection_query, [wkt_polygon])
intersected_data = cursor.fetchall()

#Function for display masrker
def display_data():

if st.button(label="Display Data"):
    # Display the intersected data on the Leafmap:
    for row in intersected_data:
        lat, lon = row
        marker = leafmap.Marker(location=(lat, lon))
        m.add_layer(marker)

polygon = m.user_roi  # Update the `polygon` variable with the drawn polygon
print(polygon)

Call the download_file function

display_data()

Display the map

m.to_streamlit(height=700)

Here is a picture after I draw a rectangle

Here is a picture after I click my function to show the data and the value of m.user_roi still none

The rectangle also will be lost.