"""Show the effect of the fill and expand options to pack.

Don't look at this source -- just look at the effects.
"""

from Tkinter import *
import string

class App:

    def __init__(self, parent):
	self.parent = parent
	self.create_widgets()

    def create_widgets(self):
	self.create_view()
	self.create_controls()

    def create_view(self):
	self.f_view = Frame(self.parent, width=300, height=200,
			    relief=SUNKEN, borderwidth=2)
	self.f_view.pack()
	self.f_view.propagate(0)
	self.top = Button(self.f_view, text="TOP", relief=GROOVE)
	self.top.pack(fill=BOTH)
	self.t1 = Button(self.f_view, text="T1", relief=GROOVE)
	self.t1.pack()
	self.t2 = Button(self.f_view, text="T2 (anchor=SW)", anchor=SW, relief=GROOVE)
	self.t2.pack()
	self.bottom = Button(self.f_view, text="BOTTOM", relief=GROOVE)
	self.bottom.pack(side=BOTTOM, fill=BOTH)
	self.targets = [self.t1, self.t2]

    def create_controls(self):
	self.v_expand = BooleanVar()
	self.v_fill = StringVar()
	self.v_fill.set(NONE)
	self.v_anchor = StringVar()
	self.v_anchor.set(CENTER)

	self.f_controls = Frame(self.parent)
	self.f_controls.pack(fill=X)

	self.b_expand = Checkbutton(self.f_controls,
				    text="Expand",
				    variable=self.v_expand,
				    command=self.set_it,
				    anchor=W)
	self.b_expand.pack(fill=X)

	self.f_fill = Frame(self.f_controls)
	self.f_fill.pack(fill=X)
	self.l_fill = Label(self.f_fill, text="Fill:", anchor=W)
	self.l_fill.pack(side=LEFT, fill=X)
	# This could be done in a loop, hey!
	self.b_fillnone = Radiobutton(self.f_fill,
				      text="NONE",
				      variable=self.v_fill,
				      value=NONE,
				      command=self.set_it)
	self.b_fillnone.pack(side=LEFT)
	self.b_fillx =    Radiobutton(self.f_fill,
				      text="X",
				      variable=self.v_fill,
				      value=X,
				      command=self.set_it)
	self.b_fillx.pack(side=LEFT)
	self.b_filly =    Radiobutton(self.f_fill,
				      text="Y",
				      variable=self.v_fill,
				      value=Y,
				      command=self.set_it)
	self.b_filly.pack(side=LEFT)
	self.b_fillboth = Radiobutton(self.f_fill,
				      text="BOTH",
				      variable=self.v_fill,
				      value=BOTH,
				      command=self.set_it)
	self.b_fillboth.pack(side=LEFT)

	self.f_anchor = Frame(self.f_controls)
	self.f_anchor.pack(fill=X)
	self.l_anchor = Label(self.f_anchor, text="Anchor:", anchor=W)
	self.l_anchor.pack(side=LEFT, fill=X)
	# This could be done in a loop, hey!
	self.b_anchorcenter = Radiobutton(
	    self.f_anchor, text="CENTER", variable=self.v_anchor,
	    value=CENTER, command=self.set_it)
	self.b_anchorcenter.pack(side=LEFT)
	self.b_anchorsw = Radiobutton(
	    self.f_anchor, text="NE", variable=self.v_anchor,
	    value=NE, command=self.set_it)
	self.b_anchorsw.pack(side=LEFT)
	# Don't show all 9 anchor options...

	self.show = Label(self.f_controls, anchor=W, justify=LEFT)
	self.show.pack(fill=X)
	self.set_it()

    def set_it(self):
	expand = self.v_expand.get()
	fill = self.v_fill.get()
	anchor = self.v_anchor.get()
	text = "w.pack(expand=%d,\nfill=%s, anchor=%s)" % (
	    expand, string.upper(fill), string.upper(anchor))
	self.show.config(text=text)
	for w in self.targets:
	    w.pack(expand=expand, fill=fill, anchor=anchor)


# Boilerplate from here on...
if __name__ == '__main__':
    root = Tk()
    app = App(root)
    root.mainloop()