How to find out height of a Canvas

[Frank Niessink]

Tim Rowe <digitig at cix.co.uk> wrote:
> How do I find out the height of a Tkinter Canvas? canvas.itemcget looks 
> promising, but it needs two arguments (I get a Tcl error if I omit the 
> second argument, or set it to None), and I can't find any documentation on 
> what the second argument should be (or the first argument, for that 
> matter; I'm assuming /that/ should be a string containing the name of the 
> attribute).

Canvas.itemcget gets the options of an item on the canvas, not of the
canvas itself. Use Canvas.config for that, e.g.:

>>> from Tkinter import *
>>> root = Tk()
>>> c = Canvas(root)
>>> c.pack()
>>> c.config('height')
('height', 'height', 'Height', '7c', '250')

The second argument of itemcget is the option you want to know about, e.g.:
>>> tag = c.create_line(0, 0, 100, 100, arrow='both')
>>> c.itemcget(tag, 'arrow')
'both'

Cheers, Frank
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