Nested groups, ungrouped layers

[tomchadwin]

Apologies for the basic questions. Does this support:

1. Groups within groups?
2. Layers not in groups?

[Azmisov]

It doesn't support nested (tree-style) groups.

However, I was able to do "layers not in groups" or ungrouped layers by doing the following:

• set the group name to be empty string
• add the following CSS .leaflet-control-layers-group-name:empty{display:none;}

Technically, they are still grouped, but it hides the group name from the control, so it appears as though the contained layers are ungrouped. This will only work if you do not add styling to the group name wrapper (the label element). It also works with the groupCheckboxes option set to true. The plugin doesn't include the checkbox when the group name is empty, which is nice.

What do you guys think about adding a new advanced option classNames, which accepts an object of the form: { groupname: classname, ...}. Then you could add custom CSS classes to each group, and do less hacky per-group styling? For instance, you could add {"hidden_group1": "hidden"} to hide the header and style the contained layer controls to look like top-level on-off controls.