_sync_session_state()

Author: Mike Prosser

examples/simple_graph/simple_graph_panel.py

@@ -23,8 +23,7 @@
     amplitude_enum = AmplitudeEnum[amplitude_tuple[0]]
     panel.set_value("amplitude_enum", amplitude_enum)
 with col2:
-    base_frequency = st.number_input("Base Frequency", value=1.0, step=0.1)
-    panel.set_value("base_frequency", base_frequency)
+    base_frequency = st.number_input("Base Frequency", value=1.0, step=0.1, key="base_frequency")
 
 with col3:
     frequency = panel.get_value("frequency", 0.0)

src/nipanel/_convert.py

@@ -129,3 +129,12 @@ def from_any(protobuf_any: any_pb2.Any) -> object:
 
     converter = _CONVERTER_FOR_GRPC_TYPE[underlying_typename]
     return converter.to_python(protobuf_any)
+
+
+def is_supported_type(value: object) -> bool:
+    """Check if a given Python value can be converted to protobuf Any."""
+    try:
+        _get_best_matching_type(value)
+        return True
+    except TypeError:
+        return False

src/nipanel/_streamlit_panel_initializer.py

@@ -3,6 +3,7 @@
 
 import streamlit as st
 
+from nipanel._convert import is_supported_type
 from nipanel._streamlit_panel import StreamlitPanel
 from nipanel._streamlit_panel_value_accessor import StreamlitPanelValueAccessor
 from nipanel.streamlit_refresh import initialize_refresh_component
@@ -61,6 +62,7 @@ def get_panel_accessor() -> StreamlitPanelValueAccessor:
         st.session_state[PANEL_ACCESSOR_KEY] = _initialize_panel_from_base_path()
 
     panel = cast(StreamlitPanelValueAccessor, st.session_state[PANEL_ACCESSOR_KEY])
+    _sync_session_state(panel)
     refresh_component = initialize_refresh_component(panel.panel_id)
     refresh_component()
     return panel
@@ -75,3 +77,11 @@ def _initialize_panel_from_base_path() -> StreamlitPanelValueAccessor:
     if not panel_id:
         raise ValueError(f"Panel ID is empty in baseUrlPath: '{base_url_path}'")
     return StreamlitPanelValueAccessor(panel_id)
+
+
+def _sync_session_state(panel):
+    """Automatically read keyed control values from the session state."""
+    for key in st.session_state.keys():
+        value = st.session_state[key]
+        if is_supported_type(value):
+            panel.set_value(str(key), value)