If you click on the column header of a regular treeview, the
entries will get sorted by the values in that column.
That works fine for the file chooser, at least if you sort by
filename.
It works horribly for programs like Banshee that display a long
list of (artist,album,song) entries. Sort by artist, according
to the treeview, means something like “sort by artist, and insofar
two entries’ artist values agree, pick a random ordering”.
That is useless! (It is a different matter whether Banshee has
the right interface for its song list. Add a few thousand songs
and I have the feeling the UI will suffer.)
To be useful, one ought to have the option of telling the treeview
that sorting by artist really means to sort by the (artist,album,song)
tuple.
So what am I not seeing?