from Tkinter import *
import math
class HelloWorld:
def __init__(self, parent):
self.master = parent
top = Frame(parent)
top.pack(side='top')
hwframe = Frame(top)
hwframe.pack(side='top')
font = 'times 18 bold'
hwtext = Label(hwframe, text='Hello, World!', font=font)
hwtext.pack(side='top', pady=20)
rframe = Frame(top)
rframe.pack(side='top', padx=10, pady=20)
r_label = Label(rframe, text='The sine of')
r_label.pack(side='left')
self.r = StringVar()
self.r.set('1.2')
r_entry = Entry(rframe, width=6, textvariable=self.r)
r_entry.pack(side='left')
r_entry.bind('', self.comp_s)
compute = Button(rframe, text=' equals ',
command=self.comp_s, relief='flat')
compute.pack(side='left')
self.s = StringVar()
s_label = Label(rframe, textvariable=self.s, width=12)
s_label.pack(side='left')
quit_button = Button(top, text='Goodbye, GUI World!',
command=self.quit,
background='yellow',foreground='blue')
quit_button.pack(side='top', pady=5, fill='x')
self.master.bind('', self.quit)
def quit(self, event=None):
self.master.quit()
def comp_s(self, event=None):
self.s.set('%g' % math.sin(float(self.r.get())))
root = Tk()
hello = HelloWorld(root)
root.mainloop()