python Tkinter学习笔记 简单的计算器 03

zhoujun.g

'''
Created on 2013-9-27
@author: liangqianwu
'''
#_*_ coding:utf-8_*_
from Tkinter import *
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.pack(expand=YES,fill=BOTH)
self.master.title('hello Calculator')
self.master.iconname('calcl')
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,s='%s'%char:w.set(w.get()+s))
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,c=char:w.set(w.get()+''+c+''))
clearF=frame(self,BOTTOM)
button(clearF,LEFT,'Clr',lambda w=display:w.set(''))
def calc(self,display):
try:
display.set(`eval(display.get())`)
except ValueError:
display.set('ERROR')
if __name__ =='__main__':
Calculator().mainloop()