Update src/streamlit_app.py

src/streamlit_app.py

@@ -254,8 +254,15 @@ crime_dropdown = ipywidgets.Dropdown(
     options= sorted(top_10_crimes),
     description="Crime Type:")
 
-# Load geojson file.
-# gdf_counties = gpd.read_file("County_Boundary.geojson")
+# Define the path to the GeoJSON file (relative to the script's location)
+GEOJSON_PATH = Path(__file__).parent / "County_Boundary.geojson"
+
+# Load the GeoJSON file with error handling
+try:
+    gdf_counties = gpd.read_file(GEOJSON_PATH)
+except FileNotFoundError:
+    st.error("Error: 'County_Boundary.geojson' file not found in the /app/src/ directory. Please ensure the file is included in the project.")
+    st.stop()
     
 # Creat dropdown menu.
 year_dropdown = ipywidgets.Dropdown(