An updated for anyone who is interested. I have it so that you can turn off multiselect (demonstrated here) and you can on the FileTree directly assign to the value attribute to select a node, even if it isn’t populated in the tree yet. Since the nodes in the tree a populated lazily, if you pass a filepath that is a child of a child of a… a child of the bottommost node, it populates that new node and all of its intermediate parents too, and then select it.
Here it is with some other widgets for layouting
Here is the repo if anyone wants to install it and try it out. It is still buggy, so be warned
You should be able to do a pip install git+https://github.com/madeline-scyphers/panel-jstree
to install it. You will also need nodejs >= 14, which you can do yourself or through conda: conda install -c conda-forge 'nodejs>=14'
Just wanted to give an update to anyone watching and wanting to use it before I try while it is a wip.