这有什么不对？ （属性错误__len__）

Question

Given this relatively simple tk script:

import Tkinter

class buttton(Tkinter.Button):
    def __init__(self,frame,action=None):
        if action==None:
            action=self.action
        Tkinter.Button.__init__(self,frame,command=action)
        self.pack(frame)
    def action(self):
        None


root=Tkinter.Tk()
button=buttton(root)
root.mainloop()

When running this program, I am met with the rather cryptic error:

Traceback (most recent call last):
  File "C:/Users/username/Desktop/ab.py", line 14, in <module>
    button=buttton(root)
  File "C:/Users/username/Desktop/ab.py", line 8, in __init__
    self.pack(frame)
  File "C:\Python27\lib\lib-tk\Tkinter.py", line 1940, in pack_configure
    + self._options(cnf, kw))
  File "C:\Python27\lib\lib-tk\Tkinter.py", line 1162, in _options
    cnf = _cnfmerge(cnf)
  File "C:\Python27\lib\lib-tk\Tkinter.py", line 114, in _cnfmerge
    for c in _flatten(cnfs):
  File "C:\Python27\lib\lib-tk\Tkinter.py", line 1898, in __getattr__
    return getattr(self.tk, attr)
AttributeError: __len__

I would be more than happy for any help!

Answer 1

Here is your problem:

self.pack(frame)

self.pack doesn't take a frame argument. Remove frame , and it should run fine, like so:

self.pack()