Try to update shiny example

examples/shiny/app.py

@@ -0,0 +1,30 @@
+import geopandas as gpd
+from shiny import reactive
+from shiny.express import input, ui
+from shinywidgets import render_widget
+
+from lonboard import Map, ScatterplotLayer
+
+colors = {
+    "Red": [200, 0, 0],
+    "Green": [0, 200, 0],
+    "Blue": [0, 0, 200],
+}
+
+ui.input_select("color_select", "Color", choices=list(colors.keys()))
+
+
+@render_widget
+def layer():
+    gdf = gpd.read_file(gpd.datasets.get_path("naturalearth_cities"))
+    return ScatterplotLayer.from_geopandas(gdf, radius_min_pixels=2)
+
+
+@render_widget
+def map():
+    return Map(layer.widget)
+
+
+@reactive.effect
+def set_fill_color():
+    layer.widget.get_fill_color = colors[input.color_select()]