from gi.repository import Gtk
import sys
class MyWindow(Gtk.ApplicationWindow):
def __init__(self, app):
Gtk.Window.__init__(self, title="Calculator", application=app)
self.set_default_size(350, 200)
self.set_border_width(10)
# an entry
self.entry = Gtk.Entry()
# with an initial text
self.entry.set_text('0')
# text aligned on the right
self.entry.set_alignment(1)
# the text in the entry cannot be modified writing in it
self.entry.set_can_focus(False)
# a grid
grid = Gtk.Grid()
grid.set_row_spacing(5)
# to attach the entry
grid.attach(self.entry, 0, 0, 1, 1)
# the labels for the buttons
buttons = [7, 8, 9, '/',
4, 5, 6, '*',
1, 2, 3, '-',
'C', 0, '=', '+']
# each row is a ButtonBox, attached to the grid
for i in range(4):
hbox = Gtk.ButtonBox.new(Gtk.Orientation.HORIZONTAL)
hbox.set_spacing(5)
grid.attach(hbox, 0, i + 1, 1, 1)
# each ButtonBox has 4 buttons, connected to the callback function
for j in range(4):
button = Gtk.Button(label=buttons[i * 4 + j])
button.set_can_focus(False)
button.connect("clicked", self.button_clicked)
hbox.add(button)
# some variables for the calculations
self.first_number = 0
self.second_number = 0
self.counter = 0
self.operation = ""
# add the grid to the window
self.add(grid)
# callback function for all the buttons
def button_clicked(self, button):
# for the operations
if button.get_label() == '+':
self.counter += 1
if self.counter > 1:
self.do_operation()
self.entry.set_text('0')
self.operation = "plus"
elif button.get_label() == '-':
self.counter += 1
if self.counter > 1:
self.do_operation()
self.entry.set_text('0')
self.operation = "minus"
elif button.get_label() == '*':
self.counter += 1
if self.counter > 1:
self.do_operation()
self.entry.set_text('0')
self.operation = "multiplication"
elif button.get_label() == '/':
self.counter += 1
if self.counter > 1:
self.do_operation()
self.entry.set_text('0')
self.operation = "division"
# for =
elif button.get_label() == '=':
self.do_operation()
self.entry.set_text(str(self.first_number))
self.counter = 1
# for Cancel
elif button.get_label() == 'C':
self.first_number = 0
self.second_number = 0
self.counter = 0
self.entry.set_text('')
self.operation = ""
# for a digit button
else:
new_digit = int(button.get_label())
if self.entry.get_text() == 'error':
number = 0
else:
number = int(self.entry.get_text())
number = number * 10 + new_digit
if self.counter == 0:
self.first_number = number
else:
self.second_number = number
self.entry.set_text(str(number))
def do_operation(self):
if self.operation == "plus":
self.first_number += self.second_number
elif self.operation == "minus":
self.first_number -= self.second_number
elif self.operation == "multiplication":
self.first_number *= self.second_number
elif self.operation == "division":
try:
self.first_number /= self.second_number
except ZeroDivisionError:
self.first_number = 0
self.second_number = 0
self.counter = 0
self.entry.set_text('error')
self.operation = ""
return
else:
self.first_number = 0
self.second_number = 0
self.counter = 0
self.entry.set_text('error')
class MyApplication(Gtk.Application):
def __init__(self):
Gtk.Application.__init__(self)
def do_activate(self):
win = MyWindow(self)
win.show_all()
def do_startup(self):
Gtk.Application.do_startup(self)
app = MyApplication()
exit_status = app.run(sys.argv)
sys.exit(exit_status)