Issue #22068: Avoided reference loops with Variables and Fonts in Tkinter.
diff --git a/Lib/lib-tk/Tkinter.py b/Lib/lib-tk/Tkinter.py
index aade649..bf5bc28 100644
--- a/Lib/lib-tk/Tkinter.py
+++ b/Lib/lib-tk/Tkinter.py
@@ -201,6 +201,7 @@
Subclasses StringVar, IntVar, DoubleVar, BooleanVar are specializations
that constrain the type of the value returned from get()."""
_default = ""
+ _tclCommands = None
def __init__(self, master=None, value=None, name=None):
"""Construct a variable
@@ -214,7 +215,7 @@
global _varnum
if not master:
master = _default_root
- self._master = master
+ self._root = master._root()
self._tk = master.tk
if name:
self._name = name
@@ -227,9 +228,15 @@
self.set(self._default)
def __del__(self):
"""Unset the variable in Tcl."""
- if (self._tk is not None and
- self._tk.getboolean(self._tk.call("info", "exists", self._name))):
+ if self._tk is None:
+ return
+ if self._tk.getboolean(self._tk.call("info", "exists", self._name)):
self._tk.globalunsetvar(self._name)
+ if self._tclCommands is not None:
+ for name in self._tclCommands:
+ #print '- Tkinter: deleted command', name
+ self._tk.deletecommand(name)
+ self._tclCommands = None
def __str__(self):
"""Return the name of the variable in Tcl."""
return self._name
@@ -248,7 +255,20 @@
Return the name of the callback.
"""
- cbname = self._master._register(callback)
+ f = CallWrapper(callback, None, self._root).__call__
+ cbname = repr(id(f))
+ try:
+ callback = callback.im_func
+ except AttributeError:
+ pass
+ try:
+ cbname = cbname + callback.__name__
+ except AttributeError:
+ pass
+ self._tk.createcommand(cbname, f)
+ if self._tclCommands is None:
+ self._tclCommands = []
+ self._tclCommands.append(cbname)
self._tk.call("trace", "variable", self._name, mode, cbname)
return cbname
trace = trace_variable
@@ -259,7 +279,11 @@
CBNAME is the name of the callback returned from trace_variable or trace.
"""
self._tk.call("trace", "vdelete", self._name, mode, cbname)
- self._master.deletecommand(cbname)
+ self._tk.deletecommand(cbname)
+ try:
+ self._tclCommands.remove(cbname)
+ except ValueError:
+ pass
def trace_vinfo(self):
"""Return all trace callback information."""
return map(self._tk.split, self._tk.splitlist(