jf...@ms4.hinet.net wrote: > I am running a tkinter tutor downloaded from web, > https://github.com/daleathan/widget-tour-py3. there are two files > involved: > > -------------------- > #file button.py > > from tkinter import * > from tkinter.ttk import * > import infrastructure > ... > class ButtonsDemoWindow( infrastructure.DemoWindow ): > ... > def __init__( self ): > ... > ... > for c in ('Peach Puff', 'Light Blue', 'Sea Green', 'Yellow' ): > b = Button(self.frame, text=c) > b['command'] = infrastructure.callit( self.callback, c ) > b.pack( side=TOP, expand=YES, pady=2 ) > > def callback(self, color): > self.frame['background']=color > > def runDemo(): > ButtonsDemoWindow() > > ---------------------- > #file infrastructure.py > ... > class DemoWindow( Toplevel ): > ... > ... > class callit: > def __init__(self, function, *args ): > self.f = function > self.args = args > > def __call__(self, *ignored): > self.f( *self.args) > > -------------------- > I run it under the DOS box: > > D:\Works\Python\widget-tour-py3-master>python > Python 3.4.4 (v3.4.4:737efcadf5a6, Dec 20 2015, 19:28:18) [MSC v.1600 > 32 bit (Intel)] on win32 Type "help", "copyright", "credits" or > "license" for more information. > >>> import button > >>> button.runDemo() > > after the window shows up, I pressed one of the buttons and get the error > below: > >>>> Exception in Tkinter callback > Traceback (most recent call last): > File "C:\Python34\lib\tkinter\__init__.py", line 1538, in __call__ > return self.func(*args) > File "D:\Works\Python\widget-tour-py3-master\infrastructure.py", line > 216, in __call__ > self.f( *self.args) > File "D:\Works\Python\widget-tour-py3-master\button.py", line 39, in > callback > self.frame['background']=color > File "C:\Python34\lib\tkinter\__init__.py", line 1331, in __setitem__ > self.configure({key: value}) > File "C:\Python34\lib\tkinter\__init__.py", line 1324, in configure > return self._configure('configure', cnf, kw) > File "C:\Python34\lib\tkinter\__init__.py", line 1315, in _configure > self.tk.call(_flatten((self._w, cmd)) + self._options(cnf)) > _tkinter.TclError: unknown option "-background" > > > When I looked into the file tkinter\__init__.py, I found there is codes > which add conditionally a '-' onto the original cnf argument:
That is just a peculiarity of TCL; a "-" is added to the option by the Python wrapper before passing it along > 1305 def _configure(self, cmd, cnf, kw): > 1306 """Internal function.""" > ... > ... > 1313 if isinstance(cnf, str): > 1314 return self._getconfigure1(_flatten((self._w, cmd, > '-'+cnf))) > > Is it the reason this exception raised? Why is that? I can confirm the problem. It looks like the bug was introduced when the example was converted from stock tkinter to the new ttk widget set. While frame["background"] = color works when frame is a tkinter.Frame widget the newer tkinter.ttk.Frame widget uses "styles" to configure its appearance. I have not used that new feature, but with the help of http://infohost.nmt.edu/tcc/help/pubs/tkinter/web/ttk-style-layer.html and some trial and error I modified the example to use a style: $ diff -u button.py button_fixed.py --- button.py 2017-08-20 11:44:33.841839812 +0200 +++ button_fixed.py 2017-08-20 11:44:04.032426163 +0200 @@ -25,7 +25,9 @@ infrastructure.DemoWindow.__init__(self, intro, 'button.py' ) - self.frame=Frame(self) + self.style = Style(self) + self.frame=Frame(self, style="foo.TFrame") + self.frame.pack(expand=YES, fill=BOTH ) for c in ('Peach Puff', 'Light Blue', 'Sea Green', 'Yellow' ): @@ -36,7 +38,7 @@ def callback(self, color): - self.frame['background']=color + self.style.configure("foo.TFrame", background=color) def runDemo(): $ However, I'm not sure if this is the canonical way to write it... -- https://mail.python.org/mailman/listinfo/python-list
