[Tkinter-discuss] grid manager does propagate width - why?

[Helmut Jarausch]

Hi,

I have two version of a simple labeled entry widget.

import Tkinter as Tk

class LabEntry(Tk.Entry) :
  def __init__(self,root,label,**args) :
    self.Frame= Tk.Frame(root)
    Lab=Tk.Label(self.Frame,text=label)
    Lab.grid(column=0,row=0)
    Tk.Entry.__init__(self,self.Frame,**args)
    self.grid(column=1,row=0)
  
  def grid(self,**args) :
    self.Frame.grid(**args)

def Finish() :
  root.destroy()

root= Tk.Tk()
root.protocol('WM_DELETE_WINDOW',Finish)
Name= Tk.StringVar()
Name.set('')
NameF= Tk.Frame(root)
NameF.grid(column=0,row=0)
Tk.Label(NameF,text='Name :').grid(column=0,row=0)
NameE= Tk.Entry(NameF,textvariable=Name,width=25)
NameE.grid(column=1,row=0)
Tk.mainloop()

-------------------------------------------------

This version, which doesn't use LabEntry, reserves space for 25 
characters in the entry widget.

But, replacing the last 6 lines by

NameE= LabEntry(root,'Name :',textvariable=Name,width=25)
NameE.grid(column=0,row=0)
Tk.mainloop()

the (internal) entry widget has only size 0 initially.
Why?

Many thanks for a hint,
Helmut.