Creating Leaflet layer that can be toggled in layer control from CartoDB viz.json?

Question

How do I create a leaflet layer that can be toggled in the layer control from a cartodb viz.json? I have read that the cartodb.createlayer does not create a leaflet layer. It seems you can add the cartodb table, but of course that takes away the whole point of using cartodb for easy visualization. This seems like a basic function, I am a novice in terms of coding so maybe I am missing something.

Answer 1

Putting the layer control inside the cartodb callback like this seems to work, but the legend remains. Also not sure how this would apply to multiple cartodb layers, but this essentially answers my question. Setting the index value is key to getting the cartodb layer to draw above the tile layer without losing the leaflet layer control:

 var cdb_url = 'http://ovrdc.cartodb.com/api/v2/viz/52a89830-a8c1-11e4-b072->0e0c41326911/viz.json';
 cartodb.createLayer(map, cdb_url)
   .addTo(map)
   .on('done', function(crashes) {
        crashes.setZIndex(2);
        var overlayMaps = {
          "Vehicle Crashes": crashes
        };
        L.control.layers(baseMaps, overlayMaps).addTo(map);
   })
   .on('error', function(err) {
     alert("some error occurred: " + err);
   });