Adding a colormap to a Layer or FeatureGroup

Hopefully, this is just a case of I'm-Doing-It-Wrong.

I'd like to be able to associate a colormap with a specific layer (e.g. GeoJson or TopoJson layer), independently of say, another layer of just markers or just a different choropleth layer. This way, if I deselect a layer in the LayerControl, both the GeoJson layer and the associated colormap go away (which also lets me have a separate colormap per Geo/TopoJson layer).

I've tried adding the colormap to the layer itself as well as adding both the layer and colormap to a FeatureGroup, but neither of these approaches seem to work.

Have a look at: https://github.com/eddies/folium/blob/59f88bca397a600b138abfc21591373ac3a66a78/tests/test_colormap_layer.py for an example (sorry, it's not a Jupyter notebook--long story about problems w/ Jupyter and virtualenvs)

Bắt đầu với tests/test_colormap_layer.py và chạy ví dụ hiện có để hiểu cách colormap được gắn vào các layer GeoJson, TopoJson và FeatureGroup. Hoàn tất khi colormap của một layer đi theo layer đó trong LayerControl, biến mất khi layer bị bỏ chọn, trong khi các layer riêng biệt có thể giữ các colormap riêng biệt.