Thanks <@U25U0KPFT> and <@U13A9PZC0> this is exact...
# tornadofx
Thanks @carlw and @gtnarg this is exactly what I wanted to know. I've stuffed all the File handling alongside the ViewTree. However, the renaming event needs to move into the TreeCell class that I've extended. Instead of that being a String, I should use my own class (i.e. like FSItem in Carl's example)