python gui

 代码　　如下

import tkinter as tk

class jsj:

def __init__(self):

self.root = tk.Tk()

self.root.title('简易计算器')

self.mylist = []

self.result = tk.StringVar()

self.result.set(0)

self.layout()

 

self.root.mainloop()

def put(self, x):

self.mylist.append(x)

self.result.set(''.join(self.mylist))

def delete(self):

self.mylist.clear()

self.result.set(0)

def back(self):

if len(self.mylist) > 0:

del self.mylist[-1]

self.result.set(self.mylist)

def calculation(self):

expression = ''.join(self.mylist)

result = eval(expression)

self.result.set(result)

self.mylist.clear()

self.mylist.append(str(result))

def operate(self, operator):

if len(self.mylist) > 0:

if self.mylist[-1] in ['+', '-', '*', '/', '.']:

self.mylist[-1] = operator

else:

self.mylist.append(operator)

self.result.set(''.join(self.mylist))

def layout(self):

label = tk.Label(self.root, textvariable=self.result, width=20, height=2, justify='left', anchor='se')

label.grid(row=0, column=0, padx=4, pady=4, columnspan=4)

button_clear = tk.Button(self.root, text='C', width=12, command=self.delete)

button_clear.grid(row=1, column=0, columnspan=2, padx=4, pady=4)

button_back = tk.Button(self.root, text='←', width=5, command=self.back)

button_back.grid(row=1, column=2, padx=4, pady=4)

button_div = tk.Button(self.root, text='/', width=5, command=lambda: self.operate('/'))

button_div.grid(row=4, column=3, padx=4, pady=4)

button_mult = tk.Button(self.root, text='*', width=5, command=lambda: self.operate('*'))

button_mult.grid(row=3, column=3, padx=4, pady=4)

button_seven = tk.Button(self.root, text=7, width=5, command=lambda: self.put('7'))

button_seven.grid(row=2, column=0, padx=4)

button_eight = tk.Button(self.root, text=8, width=5, command=lambda: self.put('8'))

button_eight.grid(row=2, column=1, padx=4)

button_nine = tk.Button(self.root, text=9, width=5, command=lambda: self.put('9'))

button_nine.grid(row=2, column=2, padx=4)

button_sub = tk.Button(self.root, text='-', width=5, command=lambda: self.operate('-'))

button_sub.grid(row=2, column=3, padx=4, pady=4)

button_four = tk.Button(self.root, text=4, width=5, command=lambda: self.put('4'))

button_four.grid(row=3, column=0, padx=4)

button_five = tk.Button(self.root, text=5, width=5, command=lambda: self.put('5'))

button_five.grid(row=3, column=1, padx=4)

button_six = tk.Button(self.root, text=6, width=5, command=lambda: self.put('6'))

button_six.grid(row=3, column=2, padx=4)

button_add = tk.Button(self.root, text='+', width=5, command=lambda: self.operate('+'))

button_add.grid(row=1, column=3, padx=4, pady=4)

button_one = tk.Button(self.root, text=1, width=5, command=lambda: self.put('1'))

button_one.grid(row=4, column=0, padx=4)

button_two = tk.Button(self.root, text=2, width=5, command=lambda: self.put('2'))

button_two.grid(row=4, column=1, padx=4)

button_three = tk.Button(self.root, text=3, width=5, command=lambda: self.put('3'))

button_three.grid(row=4, column=2, padx=4)

button_equal = tk.Button(self.root, text='=', width=12, command=self.calculation)

button_equal.grid(row=5, column=2, columnspan=2, padx=4, rowspan=5)

button_zero = tk.Button(self.root, text=0, width=5, command=lambda: self.put('0'))

button_zero.grid(row=5, column=1, padx=4)

button_pot = tk.Button(self.root, text='.', width=5, command=lambda: self.put('.'))

button_pot.grid(row=5, column=0, padx=4, pady=4)

jsj()