我在网上找到了这个计算器代码。
我想添加一些函数,比如pow(),但它会返回错误。
错误:
按钮(powF,LEFT,'pow',lambda w = display:w.set(w.pow()))
AttributeError:StringVar实例没有属性'pow'
from Tkinter import *
import math
def frame(root, side):
w = Frame(root)
w.pack(side=side, expand=YES, fill=BOTH)
return w
def button(root, side, text, command=None):
w = Button(root, text=text, command=command)
w.pack(side=side, expand=YES, fill=BOTH)
return w
class Calculator(Frame):
def __init__(self):
Frame.__init__(self)
self.option_add('*Font', 'Verdana 20 bold')
self.pack(expand=YES, fill=BOTH)
self.master.title('tk')
self.master.iconname("calcu1ator")
display = StringVar()
Entry(self,relief=SUNKEN,textvariable=display).pack(side=TOP,expand=YES,fill=BOTH)
for key in ("123", "456", "789", "-0."):
keyF = frame(self, TOP)
for char in key:
button(keyF, LEFT, char,lambda w=display, c=char: w.set(w.get() + c))
opsF = frame(self, TOP)
for char in "+-*/=":
if char == '=':
btn = button(opsF, LEFT, char)
btn.bind('<ButtonRelease-1>',lambda e, s=self, w=display: s.calc(w), '+')
else:
btn = button(opsF, LEFT, char,lambda w=display, s=' %s '%char:w.set(w.get()+s))
clearF = frame(self, BOTTOM)
button(clearF, LEFT, 'Clr', lambda w=display: w.set(''))
#powF = frame(self, BOTTOM)
#button(powF, LEFT, 'pow', lambda w=display: pow(w,2))
def calc(self, display):
try:
display.set(eval(display.get()))
except:
display.set("ERROR")
if __name__ == '__main__':
Calculator().mainloop()
答案 0 :(得分:1)
您不能将display
作为参数提供给pow
函数,它需要一个数字。并且不要忘记设置显示。
powF = frame(self, BOTTOM)
button(powF, LEFT, 'pow', lambda w=display: w.set(pow(float(w.get()),2)))