JezK
Edit File: percolator.py
from idlelib.delegator import Delegator from idlelib.redirector import WidgetRedirector class Percolator: def __init__(self, text): # XXX would be nice to inherit from Delegator self.text = text self.redir = WidgetRedirector(text) self.top = self.bottom = Delegator(text) self.bottom.insert = self.redir.register("insert", self.insert) self.bottom.delete = self.redir.register("delete", self.delete) self.filters = [] def close(self): while self.top is not self.bottom: self.removefilter(self.top) self.top = None self.bottom.setdelegate(None) self.bottom = None self.redir.close() self.redir = None self.text = None def insert(self, index, chars, tags=None): # Could go away if inheriting from Delegator self.top.insert(index, chars, tags) def delete(self, index1, index2=None): # Could go away if inheriting from Delegator self.top.delete(index1, index2) def insertfilter(self, filter): # Perhaps rename to pushfilter()? assert isinstance(filter, Delegator) assert filter.delegate is None filter.setdelegate(self.top) self.top = filter def removefilter(self, filter): # XXX Perhaps should only support popfilter()? assert isinstance(filter, Delegator) assert filter.delegate is not None f = self.top if f is filter: self.top = filter.delegate filter.setdelegate(None) else: while f.delegate is not filter: assert f is not self.bottom f.resetcache() f = f.delegate f.setdelegate(filter.delegate) filter.setdelegate(None) def _percolator(parent): # htest # import tkinter as tk class Tracer(Delegator): def __init__(self, name): self.name = name Delegator.__init__(self, None) def insert(self, *args): print(self.name, ": insert", args) self.delegate.insert(*args) def delete(self, *args): print(self.name, ": delete", args) self.delegate.delete(*args) box = tk.Toplevel(parent) box.title("Test Percolator") x, y = map(int, parent.geometry().split('+')[1:]) box.geometry("+%d+%d" % (x, y + 175)) text = tk.Text(box) p = Percolator(text) pin = p.insertfilter pout = p.removefilter t1 = Tracer("t1") t2 = Tracer("t2") def toggle1(): (pin if var1.get() else pout)(t1) def toggle2(): (pin if var2.get() else pout)(t2) text.pack() var1 = tk.IntVar(parent) cb1 = tk.Checkbutton(box, text="Tracer1", command=toggle1, variable=var1) cb1.pack() var2 = tk.IntVar(parent) cb2 = tk.Checkbutton(box, text="Tracer2", command=toggle2, variable=var2) cb2.pack() if __name__ == "__main__": import unittest unittest.main('idlelib.idle_test.test_percolator', verbosity=2, exit=False) from idlelib.idle_test.htest import run run(_percolator)