Ok, I tried before to make a monospaced font...but I didn't know how to do it.....but now ...it works.
I use Courier New font (a monospaced font)
our $fo_fixa  =Win32::GUI::Font->new (-bold => 0,-name=>"Courier New",-size=>13);
and counting length.....
The tree:
 $TV = $w_tutor->AddTreeView(
    -name      => "Mailtool::tutor::Tree",
    -text      => "hello world!",
    -width     => $w_tutor->ScaleWidth,
    -height    => $w_tutor->ScaleHeight-40,
    -left      => 0,
    -top       => 40,
    -lines     => 1,
    -rootlines => 1,
    -buttons   => 1,
    -visible   => 1,
    -imagelist => $IL,
  -checkboxes => 1,
 -font  => $ajudes::mevesfonts::fo_fixa,
  #  -hottrack  => 1,
-----Mensaje original-----
De: Sean Healy <jalopeura@hotmail.com>
Para: vacarisses@esquerra.org <vacarisses@esquerra.org>; perl-win32-gui-users@lists.sourceforge.net <perl-win32-gui-users@lists.sourceforge.net>
Fecha: divendres, 12 / abril / 2002 15:49
Asunto: RE: [perl-win32-gui-users] Using a \t in a text of a treeview

>>I'm still trying to do to do two colums but no results. I also tryed to
>>count the length of the string and it works good on stdout but no in the
>>window ,
>It might work in the window if you used a monospaceed font, but a better
>idea is probably to use a ListView with
>-nocolumnheader => 1,
>(this option is undocumented) and just put your text in two different
>columns.  The only problem is that ListView does not indent, so you'll have
>to prepend whitespace to your entries.  And if you want images, there may
>not be a way at all to indent the images.  (In that case, you'll probably
>have to use a monospaced font.)
>If this works, please send me a copy of the successful code.  A multi-column
>treeview seems like something I'd want to have around.
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