leaflet layer control events?

There are some events that let you know when the user activates / desactivates a layer.

This may help you:

https://leafletjs.com/reference-1.4.0.html#map-baselayerchange

For example:

map.on('overlayadd', onOverlayAdd);

function onOverlayAdd(e){
    //do whatever
}

There is a "baselayerchange' event defined here http://leafletjs.com/reference.html#control-layers Just bind it to the map object and you are good to go.

map.on('baselayerchange', function(e) {
  console.log(e);
});