Support on_change callback functions and if custom key is passed use it in session state (#241)

* Support on_change callback functions and if custom key is passed use it in session state

* Use hash key

* Update tests for indentation

* Dedent

Author: blackary

Taskfile.yml

@@ -4,23 +4,24 @@ tasks:
   install-pre-commit:
     desc: Install pre-commit hooks
     cmds:
-      - pip install pre-commit
+      - uv pip install pre-commit
       - pre-commit install
     sources:
       - .pre-commit-config.yaml
 
   install-package:
     desc: Install the package
     cmds:
-      - pip install -e .
+      - uv pip install -e .
     sources:
       - requirements.txt
       - setup.py
 
   install-test-deps:
     desc: Install the dependencies for testing
     cmds:
-      - pip install -r tests/requirements.txt
+      - uv pip install -r tests/requirements.txt
+      - playwright install --with-deps
     sources:
       - tests/requirements.txt
 

pyproject.toml

@@ -4,24 +4,24 @@ line-length = 88
 [tool.ruff.lint]
 ignore = ["B008", "ISC001", "E501", "W191", "B018"]
 select = [
-  "B",
-  "E",
-  "F",
-  "W",
-  "I",
-  "N",
-  "C4",
-  "EXE",
-  "ISC",
-  "ICN",
-  "PIE",
-  "PT",
-  "RET",
-  "SIM",
-  "ERA",
-  "PLC",
-  "RUF",
-  "ARG",
+    "B",
+    "E",
+    "F",
+    "W",
+    "I",
+    "N",
+    "C4",
+    "EXE",
+    "ISC",
+    "ICN",
+    "PIE",
+    "PT",
+    "RET",
+    "SIM",
+    "ERA",
+    "PLC",
+    "RUF",
+    "ARG",
 ]
 
 

requirements.txt

@@ -1,4 +1,4 @@
-streamlit>=1.13.0
+streamlit>=1.35.0
 folium>=0.13,!=0.15.0
 jinja2
 branca

setup.py

@@ -2,7 +2,7 @@
 
 setuptools.setup(
     name="streamlit_folium",
-    version="0.23.2",
+    version="0.24.0",
     author="Randy Zwitch",
     author_email="[email protected]",
     description="Render Folium objects in Streamlit",
@@ -13,5 +13,5 @@
     include_package_data=True,
     classifiers=[],
     python_requires=">=3.9",
-    install_requires=["streamlit>=1.13.0", "folium>=0.13,!=0.15.0", "jinja2", "branca"],
+    install_requires=["streamlit>=1.35.0", "folium>=0.13,!=0.15.0", "jinja2", "branca"],
 )

streamlit_folium/__init__.py

@@ -6,7 +6,7 @@
 import re
 import warnings
 from textwrap import dedent
-from typing import Iterable
+from typing import Callable, Iterable
 
 import branca
 import folium
@@ -212,6 +212,7 @@ def st_folium(
     pixelated: bool = False,
     debug: bool = False,
     render: bool = True,
+    on_change: Callable | None = None,
 ):
     """Display a Folium object in Streamlit, returning data as user interacts
     with app.
@@ -398,11 +399,19 @@ def walk(fig):
         css_links.extend([href for _, href in getattr(elem, "default_css", [])])
         js_links.extend([src for _, src in getattr(elem, "default_js", [])])
 
+    hash_key = generate_js_hash(leaflet, key, return_on_hover)
+
+    def _on_change():
+        if key is not None:
+            st.session_state[key] = st.session_state.get(hash_key, {})
+        if on_change is not None:
+            on_change()
+
     return _component_func(
         script=leaflet,
         html=html,
         id=m_id,
-        key=generate_js_hash(leaflet, key, return_on_hover),
+        key=hash_key,
         height=height,
         width=width,
         returned_objects=returned_objects,
@@ -415,6 +424,7 @@ def walk(fig):
         pixelated=pixelated,
         css_links=css_links,
         js_links=js_links,
+        on_change=_on_change,
     )
 
 

tests/test_package.py

@@ -1,3 +1,6 @@
+from textwrap import dedent
+
+
 def test_map():
     import folium
 
@@ -8,16 +11,13 @@ def test_map():
 
     leaflet = _get_map_string(map)
     assert (
-        """var map_div = L.map(
-    "map_div",
-    {
-        center: [0.0, 0.0],
-        crs: L.CRS.EPSG3857,
-        zoom: 1,
-        zoomControl: true,
-        preferCanvas: false,
-    }
-);"""
+        dedent(
+            """var map_div = L.map(
+                "map_div",
+                {
+                    center: [0.0, 0.0],
+                    crs: L.CRS.EPSG3857,"""
+        )
         in leaflet
     )
 
@@ -54,15 +54,15 @@ def test_draw_support():
 
     assert (
         """map_div.on('draw:created', function(e) {
-    drawnItems.addLayer(e.layer);
-});"""
+                drawnItems.addLayer(e.layer);
+            });"""
         in leaflet
     )
 
     assert (
         """var draw_control_div_1 = new L.Control.Draw(
-    options
-).addTo( map_div );"""
+                options
+            ).addTo( map_div );"""
         in leaflet
     )