lazarus/examples/virtualtreeview/vst_minimal
..
Main.lfm
Main.pas
minimal_lcl.lpi
minimal_lcl.lpr
minimal_lcl.res
readme.txt
vst_minimal.ex-meta

These are some of the "official" VirtualTreeView demo projects ported to and optimized for Lazarus. 
More samples can be found at https://github.com/blikblum/VirtualTreeView-Lazarus/tree/lazarus-v5/Demos.