A calculator - the buttons are enclosed in horizontal ButtonBoxes.
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)
The layout of the ButtonBox are set with set_layout(layout)
, where layout
can be Gtk.ButtonBoxStyle.SPREAD
(buttons are evenly spread across the box), Gtk.ButtonBoxStyle.EDGE
(buttons are placed at the edges of the box), Gtk.ButtonBoxStyle.START
(buttons are grouped towards the start of the box), Gtk.ButtonBoxStyle.END
(buttons are grouped towards the end of the box), Gtk.ButtonBoxStyle.CENTER
(buttons are centered in the box).
set_child_secondary(button, is_secondary)
sets whether button
should appear in a secondary group of children. A typical use of a secondary child is the help button in a dialog. This group appears after the other children if the style is START
, SPREAD
or EDGE
, and before the other children if the style is END
. If the style is START
or END
, then the secondary children are aligned at the other end of the button box from the main children. For the other styles, they appear immediately next to the main children.
set_child_non_homogeneous(button, is_non_homogeneous)
sets whether the child is exempted from homogeneous sizing. Default value is False
.
set_spacing(spacing)
sets the spacing, in pixels, between the buttons of the box.
In this sample we used the following:
GtkButtonBox
GtkBox
GtkButton
GtkEntry
GtkGrid