Label position on Homebrew Pmw Megawidget

[Greg]

I'm trying to create a megawidget for file selection that contains a
Label, EntryField, and Browse Button (that will open a tkFileDialog). 
The label positioning won't cooperate however, could anyone help with
this?

Here's what I want:
labelpos='w':
           ---------------------- ------------
Filename:  |c:\directory\file   | |Browse... |
           ---------------------- ------------   

No matter what I set as labelpos, the label will not end up on the
same row as the other widgets.  Some others are also not working as
expected:

labelpos='w':
    ---------------------- ------------
    |c:\directory\file   | |Browse... |
    ---------------------- ------------   
Filename: 

My code is below.  I've tried different grid(row,column) values for
the widgets, but that didn't seem to help.


Can anyone help with this?  It's driving me nuts! I imagine I'm doing
something wrong with the createlabel() method, or something else
trivially simple...

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#!/bin/python
#Running standalone will demo the above ascii pic, plus some others:

import Pmw
import Tkinter
from Tkinter import *
import tkFileDialog

class FileSelect(Pmw.MegaWidget):
  """ Megawidget containing Pmw.Entryfield and a Browse button 
      for file selection
  """

  def __init__ (self, parent=None, **kw):
    # Define the megawidget options
    optiondefs = (
                   ('labelmargin', 0,    Pmw.INITOPT),
                   ('labelpos',    None, Pmw.INITOPT),
                 )
    self.defineoptions(kw, optiondefs)

    # Initialise base class (after defining options)
    Pmw.MegaWidget.__init__(self, parent)

    # Create the components
    interior = self.interior()
        
    # Create a label
    self.createlabel(interior, childRows=2, childCols=1)

    # Create the Entryfield component
    self.entryfield = self.createcomponent('filename',      # Name
                                           (),              # Aliases
                                           None,            # Group
                                           Pmw.EntryField,  # Class
                                           (interior,),     #
Constructor Args
                                          )
    self.entryfield.grid(row=1, column=1)

    # Create the Browse Button
    self.browsebutton = self.createcomponent('browsebutton', # Name
                                             (),             # Aliases
                                             None,           # Group
                                             Tkinter.Button, # Class
                                             interior,       #
Constructor Args
                                             text="Browse...",
                                             command=self.getFileName
                                            )
    self.browsebutton.grid(row=1, column=2)
    
    # Check keywords and initialise options
    self.initialiseoptions()

  #------------------------------------------------------------------
  # Popup a file select dialog and fill in the entry field with the
  # chose filename
  #------------------------------------------------------------------
  
  def getFileName (self):
    dialog = tkFileDialog.Open()
    fname = dialog.show()
    if fname != "":
      self.entryfield.setvalue(fname)

# Standalone demo
if __name__ == "__main__":
  root = Tkinter.Tk()

  # Create and pack a FileSelect widgets
  widgets = []

  widgets.append(FileSelect(labelpos='n', label_text="north"))
  widgets.append(FileSelect(labelpos='e', label_text="east"))
  widgets.append(FileSelect(labelpos='s', label_text="south"))
  widgets.append(FileSelect(labelpos='w', label_text="west"))
  widgets.append(FileSelect(labelpos='ws', label_text="westsouth"))
  widgets.append(FileSelect(labelpos='wn', label_text="westnorth"))
  widgets.append(FileSelect(labelpos='sw', label_text="southwest"))
  widgets.append(FileSelect(labelpos='nw', label_text="northwest"))

  map(lambda w: w.pack(pady=20), widgets)
  root.mainloop()

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