I am looking for a nice plugin with working examples to group layers in OL 2.11/2.13.1 LayerSwitcher. I found several emails and posts explainig that GeoExt is the best way to do this, but have only access to OL.
OpenLayers – Working Example to Group Layers in LayerSwitcher
openlayers-2
Best Answer
There is a "unofficial" Control called OpenLayers.Control.LayerSwitcherGroups which you can find here:
https://raw.githubusercontent.com/rkj/openlayers/master/lib/OpenLayers/Control/LayerSwitcherGroups.js
Just include the Script after your OpenLayers.js and use it like this:
Apart from that there is a pretty old layerswitcher.js patch https://trac.osgeo.org/openlayers/ticket/1086 https://trac.osgeo.org/openlayers/attachment/ticket/1086/LayerSwitcher.js.patch Perhaps you could also use this and adapt it to the newer Layerswitcher.js version. The logic of this patch has been used for the Layer-Switcher-Control of HS-Layers where you can also find some more 'inspiration':
http://redmine.ccss.cz/projects/hslayers/repository/changes/trunk/source/HSLayers/Control/LayerSwitcher.js