每当我尝试运行我的代码时,看起来有点像这样:
from tkinter import OptionMenu, StringVar, Tk
class Foo(OptionMenu):
def __init__(self, master, options):
self.bar = StringVar()
self.bar.set(options[0])
self.bar.trace("w", lambda: self.mouseCallback("foobar"))
super().__init__(master, self.bar, *options)
def mouseCallback(self, baz):
print(baz)
def mainCycle():
while True:
root.update()
if __name__ == "__main__":
opts = ["A", "LONG", "LIST", "OF", "OPTIONS"]
root = Tk()
foobarbaz = Foo(root, opts)
foobarbaz.pack()
mainCycle()
我收到以下错误:
Exception in Tkinter callback
Traceback (most recent call last):
File "C:\Program Files\Python35\lib\tkinter\__init__.py", line 1549, in __call__
return self.func(*args)
File "C:\Program Files\Python35\lib\tkinter\__init__.py", line 3285, in __call__
self.__var.set(self.__value)
File "C:\Program Files\Python35\lib\tkinter\__init__.py", line 260, in set
return self._tk.globalsetvar(self._name, value)
_tkinter.TclError: can't set "PY_VAR0":
即使在很多" Stack Overflowing"之后,我仍然无法让它发挥作用。如何避免/修复此错误?
答案 0 :(得分:3)
StringVar.trace()的回调函数的签名应该类似于def callback(*args)
,因此您在StringVar.trace()中使用的lambda应该更改为:
self.bar.trace("w", lambda *args: self.mouseCallback("foobar"))