为什么我的框架子类在init中抛出一个错误？

Question

我的程序如下：

from Tkinter import * 
class TFrame(Frame): 
    def __init__(self, master=None, cnf={}, **kw): 
     Frame.__init__(self, master, cnf, kw) 

if __name__ == '__main__': 
    root = Tk() 
    tf = TFrame(root) 
    tf.pack() 
    root.mainloop() 

，我得到这个错误：

Traceback (most recent call last): 
    File "testFrame.py", line 11, in <module> 
    tf = TFrame(root) 
    File "testFrame.py", line 7, in __init__ 
    Frame.__init__(self, master, cnf, kw) 
TypeError: __init__() takes at most 3 arguments (4 given) 

怎么会我得到这里TypeError？我做类似的事情，如Tkinter.Label类。

的框架类的代码是在这里：

`class Frame(Widget): 
    """Frame widget which may contain other widgets and can have a 3D border.""" 
    def __init__(self, master=None, cnf={}, **kw): 
     """Construct a frame widget with the parent MASTER. 

     Valid resource names: background, bd, bg, borderwidth, class, 
     colormap, container, cursor, height, highlightbackground, 
     highlightcolor, highlightthickness, relief, takefocus, visual, width.""" 
     cnf = _cnfmerge((cnf, kw)) 
     extra =() 
     if 'class_' in cnf: 
      extra = ('-class', cnf['class_']) 
      del cnf['class_'] 
     elif 'class' in cnf: 
      extra = ('-class', cnf['class']) 
      del cnf['class'] 
     Widget.__init__(self, master, 'frame', cnf, {}, extra)` 

Answer 1

你需要在调用解压kw到Frame.__init__。

这应该适合你。

from Tkinter import * 
class TFrame(Frame): 
    def __init__(self, master=None, cnf={}, **kw): 
     Frame.__init__(self, master, cnf, **kw) 

if __name__ == '__main__': 
    root = Tk() 
    tf = TFrame(root) 
    tf.pack() 
    root.mainloop() 

问题是Frame使用在其调用签名，其预计的关键字参数变量量**kw，但你想传递一个字典作为一个位置参数。