Hi Monte, When you import all from tkinter, you get a number of named constants as well as the classes (constants being variables with a fixed value).
So, don't think of them as attributes, think of them as variables, which tkinter defines like: tk.W='w' tk.BOTH='both' etc. Mick On 11 March 2014 04:27, memilanuk <memila...@gmail.com> wrote: > So... this is kind of twisting my brain a bit. Not sure I understand > how/why this works the way it does. Some help or explanation would be > appreciated. > > On the one hand, I keep reading about the evils/perils of wildcard imports > and recommendations for named imports. On the other hand, it seems like > nearly every tkinter example in books, guides, tutorials that I see uses a > wildcard import. > > So I was trying to follow along some code examples from a recent book, and > also trying to use python3 as much as practical. Given that the original > book code was python 2.x and I had to change 'Tkinter' to 'tkinter', I > figured why not change to using a named import, i.e. > > import tkinter as tk > > rather than > > from Tkinter import * > > Other than having to import a 'tk.' to widget names, I figured I should be > good to go. Unfortunately not. The book had code like this: > > from tkinter import * > root = Tk() > Label(root, text="Username").grid(row=0, sticky=W) > > While what I was coming up with was more like this: > > import tkinter as tk > root = tk.Tk() > tk.Label(root, text="Username").grid(row=0, sticky='W') > > > The difference being that unless I enclosed the W attribute for the option > 'sticky=' in quotes, I got an error 'Unresolved reference 'W''. > > I asked online, and found that apparently 'W' is imported along with > 'Label', 'Entry', 'Button', 'Tk', etc. at the top level of tkinter. It > appears I can use either a wildcard import, enclose it in quotes, or use > explicit reference e.g. tk.W. > > My question is this: How / why does this make any sense, that an attribute > (W) to an option (sticky=) would be imported at the same level as widgets > themselves? Is it some artifact left over from tcl, or just a bad idea that > never went away? Between having to explicitly reference every widget > already (tk.Label) and having to be extra specific with options like > sticky... I'm starting to see why everyone uses wildcard imports when it > comes to tkinter! > > Thanks, > > Monte > > _______________________________________________ > Tkinter-discuss mailing list > Tkinter-discuss@python.org > https://mail.python.org/mailman/listinfo/tkinter-discuss _______________________________________________ Tkinter-discuss mailing list Tkinter-discuss@python.org https://mail.python.org/mailman/listinfo/tkinter-discuss
