Issue #21940: add docstrings to idlelib.WidgetRedirector.
This commit is contained in:
parent
740c730086
commit
7cca28ffa2
|
@ -1,7 +1,6 @@
|
|||
from tkinter import *
|
||||
from tkinter import TclError
|
||||
|
||||
class WidgetRedirector:
|
||||
|
||||
"""Support for redirecting arbitrary widget subcommands.
|
||||
|
||||
Some Tk operations don't normally pass through Tkinter. For example, if a
|
||||
|
@ -18,12 +17,22 @@ class WidgetRedirector:
|
|||
this command and provide a facility ('register') to intercept the widget
|
||||
operation.
|
||||
|
||||
In IDLE, the function being registered provides access to the top of a
|
||||
Percolator chain. At the bottom of the chain is a call to the original
|
||||
Tk widget operation.
|
||||
|
||||
In IDLE, WidgetRedirector is used in Percolator to intercept Text
|
||||
commands. The function being registered provides access to the top
|
||||
of a Percolator chain. At the bottom of the chain is a call to the
|
||||
original Tk widget operation.
|
||||
"""
|
||||
def __init__(self, widget):
|
||||
'''Initialize attributes and setup redirection.
|
||||
|
||||
_operations: dict mapping operation name to new function.
|
||||
widget: the widget whose tcl command is to be intercepted.
|
||||
tk: widget.tk, a convenience attribute, probably not needed.
|
||||
orig: new name of the original tcl command.
|
||||
|
||||
Since renaming to orig fails with TclError when orig already
|
||||
exists, only one WidgetDirector can exist for a given widget.
|
||||
'''
|
||||
self._operations = {}
|
||||
self.widget = widget # widget instance
|
||||
self.tk = tk = widget.tk # widget's root
|
||||
|
@ -40,22 +49,34 @@ class WidgetRedirector:
|
|||
self.widget._w)
|
||||
|
||||
def close(self):
|
||||
"Unregister operations and revert redirection created by .__init__."
|
||||
for operation in list(self._operations):
|
||||
self.unregister(operation)
|
||||
widget = self.widget; del self.widget
|
||||
orig = self.orig; del self.orig
|
||||
widget = self.widget
|
||||
tk = widget.tk
|
||||
w = widget._w
|
||||
# Restore the original widget Tcl command.
|
||||
tk.deletecommand(w)
|
||||
# restore the original widget Tcl command:
|
||||
tk.call("rename", orig, w)
|
||||
tk.call("rename", self.orig, w)
|
||||
del self.widget, self.tk # Should not be needed
|
||||
# if instance is deleted after close, as in Percolator.
|
||||
|
||||
def register(self, operation, function):
|
||||
'''Return OriginalCommand(operation) after registering function.
|
||||
|
||||
Registration adds an instance function attribute that masks the
|
||||
class instance method attribute. If a second function is
|
||||
registered for the same operation, the first function is replaced.
|
||||
'''
|
||||
self._operations[operation] = function
|
||||
setattr(self.widget, operation, function)
|
||||
return OriginalCommand(self, operation)
|
||||
|
||||
def unregister(self, operation):
|
||||
'''Return the function for the operation, or None.
|
||||
|
||||
Deleting the instance attribute unmasks the class attribute.
|
||||
'''
|
||||
if operation in self._operations:
|
||||
function = self._operations[operation]
|
||||
del self._operations[operation]
|
||||
|
@ -88,14 +109,29 @@ class WidgetRedirector:
|
|||
|
||||
|
||||
class OriginalCommand:
|
||||
'''Callable for original tk command that has been redirected.
|
||||
|
||||
Returned by .register; can be used in the function registered.
|
||||
redir = WidgetRedirector(text)
|
||||
def my_insert(*args):
|
||||
print("insert", args)
|
||||
original_insert(*args)
|
||||
original_insert = redir.register("insert", my_insert)
|
||||
'''
|
||||
|
||||
def __init__(self, redir, operation):
|
||||
'''Create .tk_call and .orig_and_operation for .__call__ method.
|
||||
|
||||
.redir and .operation store the input args for __repr__.
|
||||
.tk and .orig copy attributes of .redir (probably not needed).
|
||||
'''
|
||||
self.redir = redir
|
||||
self.operation = operation
|
||||
self.tk = redir.tk
|
||||
self.orig = redir.orig
|
||||
self.tk_call = self.tk.call
|
||||
self.orig_and_operation = (self.orig, self.operation)
|
||||
self.tk = redir.tk # redundant with self.redir
|
||||
self.orig = redir.orig # redundant with self.redir
|
||||
# These two could be deleted after checking recipient code.
|
||||
self.tk_call = redir.tk.call
|
||||
self.orig_and_operation = (redir.orig, operation)
|
||||
|
||||
def __repr__(self):
|
||||
return "OriginalCommand(%r, %r)" % (self.redir, self.operation)
|
||||
|
@ -104,7 +140,10 @@ class OriginalCommand:
|
|||
return self.tk_call(self.orig_and_operation + args)
|
||||
|
||||
|
||||
def _widget_redirector(parent):
|
||||
def _widget_redirector(parent): # htest #
|
||||
from tkinter import Tk, Text
|
||||
import re
|
||||
|
||||
root = Tk()
|
||||
root.title("Test WidgetRedirector")
|
||||
width, height, x, y = list(map(int, re.split('[x+]', parent.geometry())))
|
||||
|
@ -113,13 +152,16 @@ def _widget_redirector(parent):
|
|||
text.pack()
|
||||
text.focus_set()
|
||||
redir = WidgetRedirector(text)
|
||||
global previous_tcl_fcn
|
||||
def my_insert(*args):
|
||||
print("insert", args)
|
||||
previous_tcl_fcn(*args)
|
||||
previous_tcl_fcn = redir.register("insert", my_insert)
|
||||
original_insert(*args)
|
||||
original_insert = redir.register("insert", my_insert)
|
||||
root.mainloop()
|
||||
|
||||
if __name__ == "__main__":
|
||||
import unittest
|
||||
## unittest.main('idlelib.idle_test.test_widgetredir',
|
||||
## verbosity=2, exit=False)
|
||||
|
||||
from idlelib.idle_test.htest import run
|
||||
run(_widget_redirector)
|
||||
|
|
Loading…
Reference in New Issue