Ah okay, now I have a clue what you mean
To receive dropped files from Windows Explorer in your Application:
WM_DROPFILES,
DragAcceptFiles. You will find a lot of example code with these two search terms.
Once you get the FileName of the dropped file(s), you have to gather the required information (size, file type and so on) to display it in your tree view. (Search for e.g.
GetFileSize and/or browse your Delphi Help
)
On information how to add entries with System Images (<-
ShGetFileInfo) you may want to search for a tutorial regarding TTreeView (I don't any now, sorry - but maybe the Delphi Help is useful for you as well).
Or you use the even more powerful VirtualTreeView - if you're okay with German, I got a Tutorial for you:
http://www.delphi-treff.de/tutorials...rtualtreeview/