🚀 go-pugleaf

Using BDS2006 on WIN XP SP2

I have a listbox that I want to add several strings with a single tab in 
each string to space them within the listbox.

Example Test Application\tc:\ProgramFiles\Testing

I am using the following extract in the listbox OnDrawItem event.

void __fastcall TfrmMain::lbTESTDrawItem(TWinControl *Control,
      int Index, TRect &Rect, TOwnerDrawState State)
{
  // some code removed.
 // Item would hold each string in the listbox i.e. Test 
Application\tc:\ProgramFiles\Testing

  DRAWTEXTPARAMS dtp;
  dtp.cbSize = sizeof(dtp);
  dtp.iTabLength = 25;
  dtp.iLeftMargin = 0;
  dtp.iRightMargin = 0;

  r = Rect;
  r.Right -= 55; // <== Adjust size of Rect, WHY???
  DrawTextEx(lb->Canvas->Handle,
     Item.c_str(),
     Item.Length(),
     &r,
     DT_LEFT | DT_SINGLELINE | DT_NOCLIP | DT_VCENTER |
     DT_EXPANDTABS | DT_TABSTOP | DT_PATH_ELLIPSIS,
     &dtp);
// some code removed.
}

I find that I have adjust the Rect available by using the OnDrawItem event 
by approx 55 pixels (in this case) to get the pathname to display the 
'ellipsis'.  I don't really understand why as I have passed the size of the 
TabLength.  The only thing I can think of is that it has some thing to do 
with Logical units and device units and the TAB is not being compensated 
for.

Can anyone help?

thanks
daryl